Method and apparatus for transmitting and receiving reference signals in wireless communication

ABSTRACT

A base station includes a controller configured to configure an MRS resource set comprising a group of MRS resources, each MRS resource comprising a set of MRS antenna ports. If at least two MRS antenna ports belong to a same MRS resource, then the at least two MRS antenna ports are quasi co-located with respect to a first set of QCL parameters, else if the at least two MRS antenna ports belong to a same MRS resource set, then the at least two MRS antenna ports are quasi co-located with respect to a second set of QCL parameters, and else the at least two MRS antenna ports are not quasi co-located with respect to either the first set or the second set of QCL parameters. The MRS is a CSI-RS for estimating a CSI and at least one of the first set and the second set of QCL parameters.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIMS OF PRIORITY

This application claims priority under 35 U.S.C. § 119(e) to: U.S.Provisional Patent Application No. 62/316,159 filed on Mar. 31, 2016;U.S. Provisional Patent Application No. 62/361,433 filed on Jul. 12,2016; and U.S. Provisional Patent Application No. 62/402,466 filed onSep. 30, 2016. The above-identified provisional patent applications arehereby incorporated by reference in their entirety.

TECHNICAL FIELD

This disclosure relates generally to wireless communication systems.More specifically, this disclosure relates to method and apparatus forthe configuration and transmission of the up-link demodulation referencesignals (UL-DMRS). The present disclosure also relates to supportingsignaling of quasi-colocation of antenna ports or beams fortransmissions from user equipments (UEs) to a base station or fortransmissions from a base station to UEs.

BACKGROUND

Wireless communication has been one of the most successful innovationsin modern history. Recently, the number of subscribers to wirelesscommunication services exceeded five billion and continues to growquickly. The demand of wireless data traffic is rapidly increasing dueto the growing popularity among consumers and businesses of smart phonesand other mobile data devices, such as tablets, “note pad” computers,net books, eBook readers, and machine type of devices. In order to meetthe high growth in mobile data traffic and support new applications anddeployments, improvements in radio interface efficiency and coverage isof paramount importance.

SUMMARY

Various embodiments of the present disclosure provide methods andapparatuses for quasi co-location of antenna ports and beams for newradio. Various embodiments of the present disclosure also provideup-link demodulation reference symbol generation and placement forenhanced up-link multi-user MIMO communications.

In a first embodiment, a base station includes a controller configuredto configure a measurement reference signal (MRS) resource setcomprising a group of MRS resources, each MRS resource comprising a setof respective MRS antenna ports, wherein if at least two MRS antennaports belong to a same MRS resource, then the at least two MRS antennaports are quasi co-located with respect to a first set of quasico-located large scale channel parameters (QCL parameters), else if theat least two MRS antenna ports belong to a same MRS resource set, thenthe at least two MRS antenna ports are quasi co-located with respect toa second set of QCL parameters, and else the at least two MRS antennaports are not quasi co-located with respect to either the first set orthe second set of QCL parameters unless indicated otherwise, atransceiver configured to transmit the MRS resource set to a userequipment, wherein the MRS is a channel state information referencesignal (CSI-RS) for estimating a CSI and at least one of the first setof QCL parameters and the second set of QCL parameters.

In a second embodiment, a user equipment (UE) includes a transceiverconfigured to receive a measurement reference signal (MRS) resource setcomprising a group of MRS resources, each MRS resource comprising a setof respective MRS antenna ports, wherein if at least two MRS antennaports belong to a same MRS resource, then the at least two MRS antennaports are quasi co-located with respect to a first set of quasico-located large scale channel parameters (QCL parameters), else if theat least two MRS antenna ports belong to a same MRS resource set, thenthe at least two MRS antenna ports are quasi co-located with respect toa second set of QCL parameters, and else the at least two MRS antennaports are not quasi co-located with respect to either the first set orthe second set of QCL parameters unless indicated otherwise, and acontroller configured to be configured the measurement reference signal(MRS) resource set, wherein the MRS is a channel state informationreference signal (CSI-RS) for estimating a CSI and at least one of thefirst set of QCL parameters and the second set of QCL parameters.

In a third embodiment, A method for operating a base station, the methodincludes configuring a measurement reference signal (MRS) resource setcomprising a group of MRS resources, each MRS resource comprising a setof respective MRS antenna ports, wherein if at least two MRS antennaports belong to a same MRS resource, then the at least two MRS antennaports are quasi co-located with respect to a first set of quasico-located large scale channel parameters (QCL parameters), else if theat least two MRS antenna ports belong to a same MRS resource set, thenthe at least two MRS antenna ports are quasi co-located with respect toa second set of QCL parameters, and else the at least two MRS antennaports are not quasi co-located with respect to either the first set orthe second set of QCL parameters unless indicated otherwise, andtransmitting the MRS resource set to a user equipment, wherein the MRSis a channel state information reference signal (CSI-RS) for estimatinga CSI and at least one of the first set of QCL parameters and the secondset of QCL parameters.

In a fourth embodiment, A base station includes a transceiver configuredto transmit Physical Uplink Shared Channel (PUSCH) transmissionparameters to a user equipment (UE), and a controller configured toconfigure the uplink PUSCH transmission parameters including a cyclicshift, a orthogonal cover code (OCC) and comb offset parameters O(λ)(0)and O(λ)(1), wherein for up-to eight LIE multi user (MU)—multi inputmulti output (MIMO) with one layer per UE, the comb offset parametersO(λ)(0) and O(λ)(1) are determined according to a following table:

Cyclic Shift Field in uplink-related downlink control information (DCI)format [O^((λ))(0) O^((λ))(1)] 000 [0 0] 001 [0 0] 010 [0 0] 011 [1 1]100 [1 1] 101 [1 1] 110 [1 1] 111 [0 0]

In a fifth embodiment, a user equipment includes a transceiverconfigured to receive Physical Uplink Shared Channel (PUSCH)transmission parameters to UE, and a controller configured to generate aDemodulation reference signal (DMRS) sequence using uplink PUSCHtransmission parameters, wherein the uplink PUSCH transmissionparameters includes a cyclic shift, a orthogonal cover code (OCC) andcomb offset parameters O(λ)(0) and O(λ)(1), wherein for up-to eight UEmulti user (MU)—multi input multi output with one layer per UE, the comboffset parameters O(λ)(0) and O(λ)(1) are determined according to afollowing table:

Cyclic Shift Field in uplink-related downlink control information (DCI)format [O^((λ))(0) O^((λ))(1)] 000 [0 0] 001 [0 0] 010 [0 0] 011 [1 1]100 [1 1] 101 [1 1] 110 [1 1] 111 [0 0]

Other technical features may be readily apparent to one skilled in theart from the following FIGURES, descriptions, and claims.

Before undertaking the DETAILED DESCRIPTION below, it can beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document. The term “couple” and its derivativesrefer to any direct or indirect communication between two or moreelements, whether or not those elements are in physical contact with oneanother. The terms “transmit,” “receive,” and “communicate,” as well asderivatives thereof, encompass both direct and indirect communication.The terms “include” and “comprise,” as well as derivatives thereof, meaninclusion without limitation. The term “or” is inclusive, meaningand/or. The phrase “associated with,” as well as derivatives thereof,means to include, be included within, interconnect with, contain, becontained within, connect to or with, couple to or with, be communicablewith, cooperate with, interleave, juxtapose, be proximate to, be boundto or with, have, have a property of, have a relationship to or with, orthe like. The term “controller” means any device, system or part thereofthat controls at least one operation. Such a controller can beimplemented in hardware or a combination of hardware and software and/orfirmware. The functionality associated with any particular controllercan be centralized or distributed, whether locally or remotely. Thephrase “at least one of,” when used with a list of items, means thatdifferent combinations of one or more of the listed items can be used,and only one item in the list can be needed. For example, “at least oneof: A, B, and C” includes any of the following combinations: A, B, C, Aand B, A and C, B and C, and A and B and C.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for other certain words and phrases are provided throughoutthis patent document. Those of ordinary skill in the art shouldunderstand that in many if not most instances, such definitions apply toprior as well as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the present disclosure and itsadvantages, reference is now made to the following description taken inconjunction with the accompanying drawings, in which like referencenumerals represent like parts:

FIG. 1 illustrates an example wireless network according to someembodiments of the present disclosure;

FIGS. 2A and 2B illustrate example wireless transmit and receive pathsaccording to some embodiments of the present disclosure;

FIG. 3A illustrates an example user equipment according to someembodiments of the present disclosure;

FIG. 3B illustrates an example enhanced NodeB (eNB) according to someembodiments of the present disclosure;

FIG. 4 illustrates a structure of a DL Transmission Time Interval (TTI)according to embodiments of the present disclosure;

FIG. 5 illustrates an up-link allocation in the wireless communicationsystem;

FIGS. 6 and 7 describe the procedures that enable the UE to determinethe sequence value and placement within the uplink sub-frame of theuplink DMRS;

FIGS. 8 and 9 illustrate the UE operation with respect to determiningthe uplink DMRS sequences to use and their positions in the allocatedRBs according to embodiments of the present disclosure;

FIGS. 10, 11A, and 11B illustrate an example UE operation with respectto determining the uplink DMRS sequences to use and their positions inthe allocated RBs according to the embodiments of the presentdisclosure;

FIG. 12 illustrates an example transceiver 1200 comprising a largenumber of antenna elements according to embodiments of the presentdisclosure;

FIG. 13 illustrates an example construction of MRS antenna ports,configurations and configuration groups according to some embodiments ofthe present disclosure;

FIG. 14A illustrates another example construction of MRS antenna ports,configurations and configuration groups according to the embodiments ofthe present disclosure;

FIG. 14B illustrates the first alternative quasi co-located (QCL)definition for MRS according to embodiments of the present disclosure;

FIG. 14C illustrates another example QCL definition for MRS according toembodiments of the present disclosure;

FIG. 15 illustrates an example MRS pattern configurations andrelationships to QCL, where the cell-specific or UE-specific MRS patternis associated with QCL type configuration according to embodiments ofthe present disclosure;

FIG. 16A illustrates an example MRS pattern configurations andrelationships to QCL where a QCL type of configuration is associatedwith a cell-specific MRS pattern or a UE-specific MRS pattern accordingto embodiments of the present disclosure; and

FIG. 16B illustrates another example MRS pattern configurations andrelationships to QCL according to embodiments of the present disclosure.

DETAILED DESCRIPTION

FIGS. 1 through 16B, discussed below, and the various embodiments usedto describe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged wireless communication system.

The following documents and standards descriptions are herebyincorporated by reference into the present disclosure as if fully setforth herein:

3rd generation partnership project (3GPP) TS 36.211 v13.1.0, “E-UTRA,Physical channels and modulation” (“REF 1”); 3GPP TS 36.212 v13.1.0,“E-UTRA, Multiplexing and Channel coding” (“REF 2”); 3GPP TS 36.213v13.1.1, “E-UTRA, Physical Layer Procedures” (“REF 3”); 3GPP TS 36.331v12.3.0, “E-UTRA, Radio Resource Control (RRC) Protocol Specification”(“REF 4”); 3GPP TS 36.300 v13.0.0 “E-UTRA and E-UTRAN, Overalldescription, Stage 2” (“REF 5”); and 3GPP TS 36.216 v12.0.0, “E-UTRA,Medium Access Control (MAC) protocol specification” (“REF 6”).

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a ‘Beyond 4G Network’ or a‘Post LTE System’.

The 5G communication system is considered to be implemented in higherfrequency (mmWave) bands, e.g., 60 GHz bands, so as to accomplish higherdata rates. To decrease propagation loss of the radio waves and increasethe transmission distance, the beamforming, massive multiple-inputmultiple-output (MIMO), Full Dimensional MIMO (FD-MIMO), array antenna,an analog beam forming, large scale antenna techniques are discussed in5G communication systems.

In addition, in 5G communication systems, development for system networkimprovement is under way based on advanced small cells, cloud RadioAccess Networks (RANs), ultra-dense networks, device-to-device (D2D)communication, wireless backhaul, moving network, cooperativecommunication, Coordinated Multi-Points (CoMP), reception-endinterference cancellation and the like.

In the 5G system, Hybrid FSK and QAM Modulation (FQAM) and slidingwindow superposition coding (SWSC) as an advanced coding modulation(ACM), and filter bank multi carrier (FBMC), non-orthogonal multipleaccess (NOMA), and sparse code multiple access (SCMA) as an advancedaccess technology have been developed.

FIG. 1 illustrates an example wireless network 100 according to someembodiments of the present disclosure. The embodiment of the wirelessnetwork 100 shown in FIG. 1 is for illustration only. Other embodimentsof the wireless network 100 could be used without departing from thescope of this disclosure.

The wireless network 100 includes an eNodeB (eNB) 101, an eNB 102, andan eNB 103. The eNB 101 communicates with the eNB 102 and the eNB 103.The eNB 101 also communicates with at least one Internet Protocol (IP)network 130, such as the Internet, a proprietary IP network, or otherdata network.

Depending on the network type, other well-known terms may be usedinstead of “eNodeB” or “eNB,” such as “base station” or “access point.”For the sake of convenience, the terms “eNodeB” and “eNB” are used inthis patent document to refer to network infrastructure components thatprovide wireless access to remote terminals. Also, depending on thenetwork type, other well-known terms may be used instead of “userequipment” or “UE,” such as “mobile station,” “subscriber station,”“remote terminal,” “wireless terminal,” or “user device.” For the sakeof convenience, the terms “user equipment” and “UE” are used in thispatent document to refer to remote wireless equipment that wirelesslyaccesses an eNB, whether the UE is a mobile device (such as a mobiletelephone or smartphone) or is normally considered a stationary device(such as a desktop computer or vending machine).

The eNB 102 provides wireless broadband access to the network 130 for afirst plurality of user equipments (UEs) within a coverage area 120 ofthe eNB 102. The first plurality of UEs includes a UE 111, which may belocated in a small business (SB); a UE 112, which may be located in anenterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); aUE 114, which may be located in a first residence (R); a UE 115, whichmay be located in a second residence (R); and a UE 116, which may be amobile device (M) like a cell phone, a wireless laptop, a wireless PDA,or the like. The eNB 103 provides wireless broadband access to thenetwork 130 for a second plurality of UEs within a coverage area 125 ofthe eNB 103. The second plurality of UEs includes the UE 115 and the UE116. In some embodiments, one or more of the eNBs 101-103 maycommunicate with each other and with the UEs 111-116 using 5G, long-termevolution (LTE), LTE-A, WiMAX, or other advanced wireless communicationtechniques.

Dotted lines show the approximate extents of the coverage areas 120 and125, which are shown as approximately circular for the purposes ofillustration and explanation only. It should be clearly understood thatthe coverage areas associated with eNBs, such as the coverage areas 120and 125, may have other shapes, including irregular shapes, dependingupon the configuration of the eNBs and variations in the radioenvironment associated with natural and man-made obstructions.

As described in more detail below, one or more of BS 101, BS 102 and BS103 include 2D antenna arrays as described in embodiments of the presentdisclosure. In some embodiments, one or more of BS 101, BS 102 and BS103 support quasi co-location of antenna ports and beams for new radioand up-link demodulation reference symbol generation and placement forenhanced up-link multi-user MIMO communications.

Although FIG. 1 illustrates one example of a wireless network 100,various changes may be made to FIG. 1. For example, the wireless network100 could include any number of eNBs and any number of UEs in anysuitable arrangement. Also, the eNB 101 could communicate directly withany number of UEs and provide those UEs with wireless broadband accessto the network 130. Similarly, each eNB 102-103 could communicatedirectly with the network 130 and provide UEs with direct wirelessbroadband access to the network 130. Further, the eNB 101, 102, and/or103 could provide access to other or additional external networks, suchas external telephone networks or other types of data networks.

FIGS. 2A and 2B illustrate example wireless transmit and receive pathsaccording to some embodiments of the present disclosure. In thefollowing description, a transmit path 200 may be described as beingimplemented in an eNB (such as eNB 102), while a receive path 250 may bedescribed as being implemented in a UE (such as UE 116). However, itwill be understood that the receive path 250 could be implemented in aneNB and that the transmit path 200 could be implemented in a UE. In someembodiments, the receive path 250 is configured to support quasico-location of antenna ports and beams for new radio and up-linkdemodulation reference symbol generation and placement for enhancedup-link multi-user MIMO communications.

The transmit path 200 includes a channel coding and modulation block205, a serial-to-parallel (S-to-P) block 210, a size N Inverse FastFourier Transform (IFFT) block 215, a parallel-to-serial (P-to-S) block220, an add cyclic prefix block 225, and an up-converter (UC) 230. Thereceive path 250 includes a down-converter (DC) 255, a remove cyclicprefix block 260, a serial-to-parallel (S-to-P) block 265, a size N FastFourier Transform (FFT) block 270, a parallel-to-serial (P-to-S) block275, and a channel decoding and demodulation block 280.

In the transmit path 200, the channel coding and modulation block 205receives a set of information bits, applies coding (such as alow-density parity check (LDPC) coding), and modulates the input bits(such as with Quadrature Phase Shift Keying (QPSK) or QuadratureAmplitude Modulation (QAM)) to generate a sequence of frequency-domainmodulation symbols. The serial-to-parallel block 210 converts (such asde-multiplexes) the serial modulated symbols to parallel data in orderto generate N parallel symbol streams, where N is the IFFT/FFT size usedin the eNB 102 and the UE 116. The size N IFFT block 215 performs anIFFT operation on the N parallel symbol streams to generate time-domainoutput signals. The parallel-to-serial block 220 converts (such asmultiplexes) the parallel time-domain output symbols from the size NIFFT block 215 in order to generate a serial time-domain signal. The addcyclic prefix block 225 inserts a cyclic prefix to the time-domainsignal. The up-converter 230 modulates (such as up-converts) the outputof the add cyclic prefix block 225 to an RF frequency for transmissionvia a wireless channel. The signal may also be filtered at basebandbefore conversion to the RF frequency.

A transmitted RF signal from the eNB 102 arrives at the UE 116 afterpassing through the wireless channel, and reverse operations to those atthe eNB 102 are performed at the UE 116. The down-converter 255down-converts the received signal to a baseband frequency, and theremove cyclic prefix block 260 removes the cyclic prefix to generate aserial time-domain baseband signal. The serial-to-parallel block 265converts the time-domain baseband signal to parallel time domainsignals. The size N FFT block 270 performs an FFT algorithm to generateN parallel frequency-domain signals. The parallel-to-serial block 275converts the parallel frequency-domain signals to a sequence ofmodulated data symbols. The channel decoding and demodulation block 280demodulates and decodes the modulated symbols to recover the originalinput data stream.

Each of the eNBs 101-103 may implement a transmit path 200 that isanalogous to transmitting in the downlink to UEs 111-116 and mayimplement a receive path 250 that is analogous to receiving in theuplink from UEs 111-116. Similarly, each of UEs 111-116 may implement atransmit path 200 for transmitting in the uplink to eNBs 101-103 and mayimplement a receive path 250 for receiving in the downlink from eNBs101-103.

Each of the components in FIGS. 2A and 2B can be implemented using onlyhardware or using a combination of hardware and software/firmware. As aparticular example, at least some of the components in FIGS. 2A and 2Bmay be implemented in software, while other components may beimplemented by configurable hardware or a mixture of software andconfigurable hardware. For instance, the FFT block 270 and the IFFTblock 215 may be implemented as configurable software algorithms, wherethe value of size N may be modified according to the implementation.

Furthermore, although described as using FFT and IFFT, this is by way ofillustration only and should not be construed to limit the scope of thisdisclosure. Other types of transforms, such as Discrete FourierTransform (DFT) and Inverse Discrete Fourier Transform (IDFT) functions,could be used. It will be appreciated that the value of the variable Nmay be any integer number (such as 1, 2, 3, 4, or the like) for DFT andIDFT functions, while the value of the variable N may be any integernumber that is a power of two (such as 1, 2, 4, 8, 16, or the like) forFFT and IFFT functions.

Although FIGS. 2A and 2B illustrate examples of wireless transmit andreceive paths, various changes may be made to FIGS. 2A and 2B. Forexample, various components in FIGS. 2A and 2B could be combined,further subdivided, or omitted and additional components could be addedaccording to particular needs. Also, FIGS. 2A and 2B are meant toillustrate examples of the types of transmit and receive paths thatcould be used in a wireless network. Any other suitable architecturescould be used to support wireless communications in a wireless network.

FIG. 3A illustrates an example UE 116 according to some embodiments ofthe present disclosure. The embodiment of the UE 116 illustrated in FIG.3A is for illustration only, and the UEs 111-115 of FIG. 1 could havethe same or similar configuration. However, UEs come in a wide varietyof configurations, and FIG. 3A does not limit the scope of thisdisclosure to any particular implementation of a UE.

The UE 116 includes an antenna 305, a radio frequency (RF) transceiver310, transmit (TX) processing circuitry 315, a microphone 320, andreceive (RX) processing circuitry 325. The UE 116 also includes aspeaker 330, a main processor 340, an input/output (I/O) interface (IF)345, a keypad 350, a display 355, and a memory 360. The memory 360includes a basic operating system (OS) program 361 and one or moreapplications 362.

The RF transceiver 310 receives, from the antenna 305, an incoming RFsignal transmitted by an eNB of the network 100. The RF transceiver 310down-converts the incoming RF signal to generate an intermediatefrequency (IF) or baseband signal. The IF or baseband signal is sent tothe RX processing circuitry 325, which generates a processed basebandsignal by filtering, decoding, and/or digitizing the baseband or IFsignal. The RX processing circuitry 325 transmits the processed basebandsignal to the speaker 330 (such as for voice data) or to the mainprocessor 340 for further processing (such as for web browsing data).

The TX processing circuitry 315 receives analog or digital voice datafrom the microphone 320 or other outgoing baseband data (such as webdata, e-mail, or interactive video game data) from the main processor340. The TX processing circuitry 315 encodes, multiplexes, and/ordigitizes the outgoing baseband data to generate a processed baseband orIF signal. The RF transceiver 310 receives the outgoing processedbaseband or IF signal from the TX processing circuitry 315 andup-converts the baseband or IF signal to an RF signal that istransmitted via the antenna 305.

The main processor 340 can include one or more processors or otherprocessing devices and execute the basic OS program 361 stored in thememory 360 in order to control the overall operation of the UE 116. Forexample, the main processor 340 could control the reception of forwardchannel signals and the transmission of reverse channel signals by theRF transceiver 310, the RX processing circuitry 325, and the TXprocessing circuitry 315 in accordance with well-known principles. Insome embodiments, the main processor 340 includes at least onemicroprocessor or microcontroller.

The main processor 340 is also capable of executing other processes andprograms resident in the memory 360, such as operations for channelquality measurement and reporting for systems having 2D antenna arraysas described in embodiments of the present disclosure as described inembodiments of the present disclosure. The main processor 340 can movedata into or out of the memory 360 as required by an executing process.In some embodiments, the main processor 340 is configured to execute theapplications 362 based on the OS program 361 or in response to signalsreceived from eNBs or an operator. The main processor 340 is alsocoupled to the I/O interface 345, which provides the UE 116 with theability to connect to other devices such as laptop computers andhandheld computers. The I/O interface 345 is the communication pathbetween these accessories and the main controller 340.

The main processor 340 is also coupled to the keypad 350 and the displayunit 355. The operator of the UE 116 can use the keypad 350 to enterdata into the UE 116. The display 355 may be a liquid crystal display orother display capable of rendering text and/or at least limitedgraphics, such as from web sites.

The memory 360 is coupled to the main processor 340. Part of the memory360 could include a random access memory (RAM), and another part of thememory 360 could include a Flash memory or other read-only memory (ROM).

Although FIG. 3A illustrates one example of UE 116, various changes maybe made to FIG. 3A. For example, various components in FIG. 3A could becombined, further subdivided, or omitted and additional components couldbe added according to particular needs. As a particular example, themain processor 340 could be divided into multiple processors, such asone or more central processing units (CPUs) and one or more graphicsprocessing units (GPUs). Also, while FIG. 3A illustrates the UE 116configured as a mobile telephone or smartphone, UEs could be configuredto operate as other types of mobile or stationary devices.

FIG. 3B illustrates an example eNB 102 according to some embodiments ofthe present disclosure. The embodiment of the eNB 102 shown in FIG. 3Bis for illustration only, and other eNBs of FIG. 1 could have the sameor similar configuration. However, eNBs come in a wide variety ofconfigurations, and FIG. 3B does not limit the scope of this disclosureto any particular implementation of an eNB. It is noted that eNB 101 andeNB 103 can include the same or similar structure as eNB 102.

As shown in FIG. 3B, the eNB 102 includes multiple antennas 370 a-370 n,multiple RF transceivers 372 a-372 n, transmit (TX) processing circuitry374, and receive (RX) processing circuitry 376. In certain embodiments,one or more of the multiple antennas 370 a-370 n include 2D antennaarrays. The eNB 102 also includes a controller/processor 378, a memory380, and a backhaul or network interface 382.

The RF transceivers 372 a-372 n receive, from the antennas 370 a-370 n,incoming RF signals, such as signals transmitted by UEs or other eNBs.The RF transceivers 372 a-372 n down-convert the incoming RF signals togenerate IF or baseband signals. The IF or baseband signals are sent tothe RX processing circuitry 376, which generates processed basebandsignals by filtering, decoding, and/or digitizing the baseband or IFsignals. The RX processing circuitry 376 transmits the processedbaseband signals to the controller/processor 378 for further processing.

The TX processing circuitry 374 receives analog or digital data (such asvoice data, web data, e-mail, or interactive video game data) from thecontroller/processor 378. The TX processing circuitry 374 encodes,multiplexes, and/or digitizes the outgoing baseband data to generateprocessed baseband or IF signals. The RF transceivers 372 a-372 nreceive the outgoing processed baseband or IF signals from the TXprocessing circuitry 374 and up-converts the baseband or IF signals toRF signals that are transmitted via the antennas 370 a-370 n.

The controller/processor 378 can include one or more processors or otherprocessing devices that control the overall operation of the eNB 102.For example, the controller/processor 378 could control the reception offorward channel signals and the transmission of reverse channel signalsby the RF transceivers 372 a-372 n, the RX processing circuitry 376, andthe TX processing circuitry 374 in accordance with well-knownprinciples. The controller/processor 378 could support additionalfunctions as well, such as more advanced wireless communicationfunctions. For instance, the controller/processor 378 can perform theblind interference sensing (BIS) process, such as performed by a BISalgorithm, and decodes the received signal subtracted by the interferingsignals. Any of a wide variety of other functions could be supported inthe eNB 102 by the controller/processor 378. In some embodiments, thecontroller/processor 378 includes at least one microprocessor ormicrocontroller.

The controller/processor 378 is also capable of executing programs andother processes resident in the memory 380, such as a basic OS. Thecontroller/processor 378 is also capable of supporting quasi co-locationof antenna ports and beams for new radio and up-link demodulationreference symbol generation and placement for enhanced up-linkmulti-user MIMO communications as described in embodiments of thepresent disclosure. In some embodiments, the controller/processor 378supports communications between entities, such as web Real-TimeCommunication (RTC). The controller/processor 378 can move data into orout of the memory 380 as required by an executing process.

The controller/processor 378 is also coupled to the backhaul or networkinterface 382. The backhaul or network interface 382 allows the eNB 102to communicate with other devices or systems over a backhaul connectionor over a network. The interface 382 could support communications overany suitable wired or wireless connection(s). For example, when the eNB102 is implemented as part of a cellular communication system (such asone supporting 5G, LTE, or LTE-A), the interface 382 could allow the eNB102 to communicate with other eNBs over a wired or wireless backhaulconnection. When the eNB 102 is implemented as an access point, theinterface 382 could allow the eNB 102 to communicate over a wired orwireless local area network or over a wired or wireless connection to alarger network (such as the Internet). The interface 382 includes anysuitable structure supporting communications over a wired or wirelessconnection, such as an Ethernet or RF transceiver.

The memory 380 is coupled to the controller/processor 378. Part of thememory 380 could include a RAM, and another part of the memory 380 couldinclude a Flash memory or other ROM. In certain embodiments, a pluralityof instructions, such as a BIS algorithm is stored in memory. Theplurality of instructions are configured to cause thecontroller/processor 378 to perform the BIS process and to decode areceived signal after subtracting out at least one interfering signaldetermined by the BIS algorithm.

As described in more detail below, the transmit and receive paths of theeNB 102 (implemented using the RF transceivers 372 a-372 n, TXprocessing circuitry 374, and/or RX processing circuitry 376) supportcommunication with aggregation of FDD cells and TDD cells.

Although FIG. 3B illustrates one example of an eNB 102, various changesmay be made to FIG. 3B. For example, the eNB 102 could include anynumber of each component shown in FIG. 3. As a particular example, anaccess point could include a number of interfaces 382, and thecontroller/processor 378 could support routing functions to route databetween different network addresses. As another particular example,while shown as including a single instance of TX processing circuitry374 and a single instance of RX processing circuitry 376, the eNB 102could include multiple instances of each (such as one per RFtransceiver).

FIG. 4 illustrates a structure of a DL Transmission Time Interval (TTI)according to embodiments of the present disclosure.

Referring to FIG. 4, DL signaling uses Orthogonal Frequency DivisionMultiplexing (OFDM) and a DL TTI has a duration of one millisecond (ms)and includes N=14 OFDM symbols in the time domain (or two slots) and KResource Blocks (RBs) in the frequency domain. A first type of ControlCHannels (CCHs) is transmitted in a first N₁ OFDM symbols 410 (includingno transmission, N₁=0). A remaining N−N₁ OFDM symbols are used primarilyfor transmitting PDSCHs 420 and, in some RBs of a TTI, for transmittinga second type of CCHs (ECCHs) 430. Each RB consists of N_(SC) ^(RB)sub-carriers, or Resource Elements (REs), and a UE is allocatedM_(PDSCH) RBs for a total of M_(SC) ^(PDSCH)=M_(PDSCH)·N_(SC) ^(RB) REsfor the PDSCH transmission BW. A unit of 1 RB in frequency and of 1 slotin time is referred to as Physical RB (PRB).

FIG. 5 illustrates an up-link allocation in the wireless communicationsystem. A UE is allocated a set of N RBs (resource blocks) 501 to 504numbered from S to S+N−1 in the example numbering of FIG. 5. Each RBconsists of 12 sub-carriers in frequency and 14 OFDM symbols in time.The modulation samples representing the coded information beingtransmitted by the UE are placed in the PUSCH (packet up-link sharedchannel) region 502 in each RB; in FIG. 5, this is the un-shaded regionin each RB. The DMRS (demodulation reference symbols) 503, which are thepilots used to demodulate the PUSCH, are placed in 4^(th) and 11^(th)OFDM symbol in each RB. The 1^(st) 7 OFDM symbols of the RB are referredto as belonging to Slot #0 of the RB, while the 2^(nd) set of 7 OFDMsymbols are referred to as belonging to Slot #1 of the RB. Hence, theDMRS symbols 503 are placed in the 4th OFDM symbol in Slot #s 0 and 1 ofthe RB.

FIGS. 6 and 7 describe the procedures that enable the UE to determinethe sequence value and placement within the uplink sub-frame of theuplink DMRS.

Table 1, which is referenced in the procedures described in FIGS. 6 and7, is shown below.

Table 1: Cyclic Shift and OCC Indication Table

TABLE 1 Cyclic Shift and OCC Indication Table Cyclic Shift Field inuplink-related n⁽²⁾ _(DMRS, λ) [w^((λ))(0) w^((λ))(1)] DCI format [3] λ= 0 λ = 1 λ = 2 λ = 3 λ = 0 λ = 1 λ = 2 λ = 3 000 0 6 3 9 [1 1] [1 1] [1−1] [1 −1] 001 6 0 9 3 [1 −1] [1 −1] [1 1] [1 1] 010 3 9 6 0 [1 −1] [1−1] [1 1] [1 1] 011 4 10 7 1 [1 1] [1 1] [1 1] [1 1] 100 2 8 5 11 [1 1][1 1] [1 1] [1 1] 101 8 2 11 5 [1 −1] [1 −1] [1 −1] [1 −1] 110 10 4 1 7[1 −1] [1 −1] [1 −1] [1 −1] 111 9 3 0 6 [1 1] [1 1] [1 −1] [1 −1]

Referring to FIG. 6: 1. In step 601, the eNB indicates the uplink PUSCHtransmission parameters to UE. These include the N contiguous RBs withindices S through (S+N−1), the parameter λ indicating the number oflayers as (2+1), the cyclic shift field value v indexing each row ofTable 1, as well as other parameters described in REF 1. The number oflayers (X+1) can be at-most 4.

2. In step 602, the UE calculates the length of the up-link DMRSsequence as M_(SC) ^(RS)=M_(SC) ^(RB).N, where M_(SC) ^(RB)=12 is thenumber of sub-carriers per OFDM symbol per RB.

3. In step 603, the UE generates the DMRS sequence r(n)], n=0, . . . ,M_(SC) ^(RS)−1, using: 3.a. the value of the parameter from Table 1obtained from the row corresponding to the cyclic shift field value vand the column for the λ value among the set of columns corresponding tothe n_(DRMS,λ) ⁽²⁾ parameter; and 3.b. the other parameters indicated bythe eNB in (1) above.

4. In step 604, the UE generates the uplink DMRS sequencesr₀(n)=w(λ)w^((λ))(0).r(n) and r₁(n)=w^((λ))(1).r(n) using the values ofthe cover code parameters w^((λ))(0) and w^((λ))(1) corresponding to thevth row and the column for the λ value among the set of columnscorresponding to the [w^((λ))(0) w^((λ))(1)] parameters of Table 1. Itmay be noted that [w^((λ))(0) w^((λ))(1)]=[1±1]. w^((λ))(0) andw^((λ))(1) are the weights corresponding to the DMRS symbols in Slot #s0 and 1 of the allocation.

In step 605, the UE then maps the generated sequences r₀(n) and r₁(n) tothe uplink OFDM symbol grid as shown in FIG. 7. As in 701, the UE mapsthe values in the sequences r₀(n) and r₁(n) sequentially to thesub-carriers that make up the 4th and 11th OFDM symbols of the uplinksub-frame.

In order to perform the information reception operation, the receiver atthe eNB performs up-link channel estimation via the received DMRSsignals. A detailed description of this process is as follows.

Firstly, the frequency-domain uplink DMRS sequences for each symbol,with length equaling the number of REs per OFDM symbol in theallocation, denoted as r₀(n) and r¹(n) in the above description are asfollows.

1. For allocations larger than 3 RBs, a ZC sequence is specified as thebase frequency domain DMRS sequence; a CAZAC sequence is specifiedotherwise. The DMRS sequence corresponding to each layer is specified tobe a cyclically-shifted version of the base sequence.

2. The, as in the above description, a cover code [w^((λ))(0)w^((λ))(1)] of length 2, with possible values [1, ±1], is specified. TheDMRS sequence for each layer, multiplied by the 1st and 2nd cover codeelements, is mapped to the 4th and 11th OFDM symbols, respectively.

In the case of a pair of completely overlapping PUSCH allocations, thecorresponding pair of DMRS sequences are completely overlapping as well.Considering one of the DMRS symbols (either the 4th or the 11th), thedifferent cyclic shifts applied to overlapping DMRS sequences yield aseparation of the layer channel impulse responses (CIRs) in the timedomain, enabling per-RE channel estimation for each sequence. A largerrelative cyclic shift difference (modulo 12) yields a better CIRseparation and better channel estimation performance; the largestpossible such difference in the design in REF 1 is 6. It may be notedthat the usage of the cyclic shift property to separately performchannel estimation on overlapping DMRS sequences is only possible in thecase of a complete overlap.

In low-Doppler, i.e., low UE speed conditions, the channel coefficientcorresponding to an certain sub-carrier can be considered to be almostconstant across the OFDM symbols in sub-frame. Hence, in low-Dopplerconditions, two DMRS sequences, possibly with the same cyclic shift butwith orthogonal cover codes ([1, 1] and [1, −1]) and occupying the sameRE can be separated by adding and subtracting the received compositeDMRS signal for that RE in the 4th and 11th symbol. It may be noted thatthe usage of the orthogonal cover code (OCC) to separately performchannel estimation on overlapping DMRS sequences is possible in the caseof a complete or a partial overlap.

A combination of different values of the DMRS sequence cyclic shifts andorthogonal cover codes may be used to multiplex up-to 2 UEs with up-to 2layers each, with partially overlapping bandwidth allocations. For thespecific case with 2 UEs with 2 layers each with partially overlappingbandwidth allocations, orthogonal cover codes would be used to separatethe 2 layers of UE1 with respect to the 2 layers of UE2 over theoverlapping portions of the allocation. This would then be followed, foreach UE, by the usage of the different cyclic shifts for the layer DMRSsequences to perform channel estimation with respect to each layerseparately.

As described above, the legacy techniques in REF 1 do not allow theability to multiplex the DMRS sequences of more than 2 UEs withpartially overlapping PUSCH allocations while maintaining acceptableup-link channel estimation performance. Such an ability would provideadditional flexibility to the eNB and enhance the overall systemperformance on the up-link. This the present disclosure providestechniques to provide such UE multiplexing capability.

As mentioned in the earlier section, legacy techniques by which the UEdetermines the sequence values and position within the up-link subframeof the DMRS sequence do not allow the ability to multiplex the DMRSsequences of more than 2 UE with overlapping PUSCH allocations whilemaintaining acceptable up-link channel estimation performance. Thepresent disclosure provides techniques to allow such a capability.

Embodiment Set 1: Extensions to Existing Cyclic Shift and OCC IndicationTable

This set of embodiments discloses techniques to extend Table 1 by addingnew parameters, while retaining the mappings and interpretations of theexisting parameters, to allow the multiplexing of more than 2 UEs, eachwith possibly partially overlapping PUSCH allocations.

Embodiment Set 1.1: Support for Up-to 8 UE MU-MIMO with 1 Layer Per UE

This set of embodiments discloses techniques to extend the legacy Table1 to enable the multiplexing of the UE DMRSs in the case that: up-to 8UEs are allocated up-link PUSCH transmissions in the same sub-frame;each UE is allocated a single PUSCH layer on the up-link; and the UEPUSCH allocations may be un-equal and partially-overlapping. In anexample situation, identifying two UEs, labeled as UE1 and UE2 from outof the set of UEs with PUSCH allocations in a given sub-frame, UE1 maybe allocated a number N1 of contiguous RBs defined by starting andending RB indices S1 and E1 respectively, whereas UE2 may be allocated anumber N2 of contiguous RBs defined by starting and ending RB indices S2and E2 respectively, where N1, S1 and E1 may or may not equal N2, S2 andE2.

Embodiment Set 1.1.1

For this set of embodiments, the legacy table is extended as shown inTable 2, by the addition of a column which defines, for each value ofthe cyclic shift field and for the specific case of the number oftransmissions layers (λ+1)=1, two offset parameters, denoted by thesymbols O^((λ))(0) and O^((λ)) (1).

Table 2: Extension of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE

TABLE 2 Extension of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE Cyclic Shift Field in uplink-related DCIn⁽²⁾ _(DMRS, λ) [w^((λ))(0) w^((λ))(1)] [O^((λ))(0) O^((λ))(1)] format[3] λ = 0 λ = 1 λ = 2 λ = 3 λ = 0 λ = 1 λ = 2 λ = 3 λ = 0 000 0 6 3 9 [11] [1 1] [1 −1] [1 −1] [0 0] 001 6 0 9 3 [1 −1] [1 −1] [1 1] [1 1] [0 0]010 3 9 6 0 [1 −1] [1 −1] [1 1] [1 1] [0 0] 011 4 10 7 1 [1 1] [1 1] [11] [1 1] [1 1] 100 2 8 5 11 [1 1] [1 1] [1 1] [1 1] [1 1] 101 8 2 11 5[1 −1] [1 −1] [1 −1] [1 −1] [1 1] 110 10 4 1 7 [1 −1] [1 −1] [1 −1] [1−1] [1 1] 111 9 3 0 6 [1 1] [1 1] [1 −1] [1 −1] [0 0]

The added column has been highlighted at the right end in Table 2.

FIGS. 8 and 9 illustrate the UE operation with respect to determiningthe uplink DMRS sequences to use and their positions in the allocatedRBs according to embodiments of the present disclosure.

The motivation for this embodiment can be understood as follows. Asexplained earlier, the receiver at the eNB performs up-link channelestimation via the received DMRS signals. A combination of differentvalues of the DMRS sequence cyclic shifts and orthogonal cover codes maybe used to multiplex up-to 2 UEs with up-to 2 layers each, withpartially overlapping bandwidth allocations. For the specific case with2 UEs with 2 layers each with partially overlapping bandwidthallocations, orthogonal cover codes would be used to separate the 2layers of UE1 with respect to the 2 layers of UE2 over the overlappingportions of the allocation. This would then be followed, for each UE, bythe usage of the different cyclic shifts for the layer DMRS sequences toperform channel estimation with respect to each layer separately.

Since the cover codes have length 2, such an orthogonal separation ofthe UE DMRS irrespective of whether or not they are fully overlapping isonly possible for up-to 2 UEs.

These embodiments disclose a technique to increase the number of UEswhose DMRS sequences can be orthogonally separated via the usage of acomb structure for the DMRS, whereby the DMRS of different UEs canoccupy non-overlapping resources irrespective of whether thecorresponding allocated PUSCH resources are overlapping ornon-overlapping. This is achieved by placing the DMRS sequence values atevery other sub-carrier of the DMRS symbols as illustrated in902/903/904/905 of FIG. 9, instead of at every sub-carrier of the DMRSsymbols as in the legacy design in REF 1. The offset parameter valuesO^((λ))(0) and O^((λ))(1), with (λ+1) denoting the number of layers,determine the starting sub-carrier for the DMRS sequence placement inthe DMRS symbols in Slot #s 0 and 1 of each RB in the allocation,respectively.

Referring to FIG. 8, the detailed operation with respect to thisembodiment set is as follows.

1. In step 801, the eNB indicates the uplink PUSCH transmissionparameters to UE. These include the N contiguous RBs with indices Sthrough (S+N−1), the parameter λ indicating the number of layers as(λ+1), the cyclic shift field value v indexing each row of Table 2, aswell as other legacy parameters described in REF 1. In this set ofembodiments, λ=0 so that the number of indicated layers as (λ+1)=1.

2. In step 802, the UE calculates the length of the up-link DMRSsequence as M_(SC) ^(RS)=M_(SC) ^(RB).N/2, where M=12 is the number ofsub-carriers per OFDM symbol per RB.

3. In step 803, the UE generates the DMRS sequence r(n), with n=0, . . .└M_(SC) ^(RS)┘−1, where └x┘ represents the floor value of the parameterx, using: 3.a. the value of the n_(DMRS,λ) ⁽²⁾ parameter obtained fromthe row corresponding to the cyclic shift field value v and the λ=0column of the set of columns corresponding to the n_(DMRS,λ) ⁽²⁾parameter, and 3.b the other legacy parameters indicated by the eNB in(1) above.

4. In step 804, the UE generates the uplink DMRS sequencesr₀(n)=w^((λ))(0).r(n) and r₁(n)=w^((λ)) (1).r(n) using the values of thecover code parameters w^((λ))(0) and w^((λ))(1) corresponding to the vthrow and the λ=0 column of the set of columns corresponding to the[w^((λ))(0) w^((λ))(1)] parameters of Table 2.

In step 805, the UE then maps the generated sequences r₀(n) and r₁(n) tothe uplink OFDM symbol grid as shown in FIG. 9.

FIG. 9 illustrates an example mapping of the generated sequences r₀(n)and r₁(n) to the uplink OFDM symbol grid according to embodiments of thepresent disclosure.

As shown in 901, the mapping rule is based on the offset parametersO^((λ))(0) and O^((λ)) (1), as follows. These offset parameters aredetermined from the row corresponding to the cyclic shift field value vand the (λ=0) column corresponding to the [O^((λ))(0) O^((λ))(1)]parameters of Table 2.

1. As shown in FIG. 9, each RB consists of 12 sub-carriers in frequencyand 14 OFDM symbols in time. The sequences r₀(n) and r₁(n) are mapped tothe sub-carriers in the 4^(th) and 11^(th) OFDM symbol of each of the NRBs in the allocation, respectively.

2. The offset parameter O^((λ))(0) is used to map the sequence r₀(n) tothe 4th OFDM symbol of each of the NRBs in the allocation.

3. In one embodiment sub-set of this embodiment set, sub-carriers in anOFDM symbol are indexed sequentially, with adjacent sub-carriers beingassigned adjacent integer values. Further, sub-carrier indexing followsthe RB indexing such that if n_(Highest) is the highest sub-carrierindex in any OFDM symbol of an RB with a certain RB index R, then thelowest sub-carrier index in the next higher RB index (R+1) isn_(Highest)+1. Then the following processes take place:

3.a. The sequence r₀(n) is mapped to the alternate sub-carriers of the4^(th) OFDM symbol, starting from the lowest indexed or 2^(nd) lowestindexed sub-carrier of the lowest indexed RB, if O^((λ))(0)=0 orO^((λ))(0)=1, respectively, as illustrated in 902 and 903 of FIG. 9.

3.a.i. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4^(th) OFDM symbol, starting from the highestindexed or 2^(nd) highest indexed sub-carrier of the highest indexed RB,if O^((λ))(0)=0 or O^((λ))(0)=1, respectively.

3.a.ii. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4^(th) OFDM symbol, starting from the lowest indexedor 2^(nd) lowest indexed sub-carrier of the lowest indexed RB, ifO^((λ))(0)=1 or O^((λ))(0)=0, respectively.

3.a. iii. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4^(th) OFDM symbol, starting from the highestindexed or 2^(nd) highest indexed sub-carrier of the highest indexed RB,if O^((λ))(0)=1 or O^((λ))(0)=0, respectively.

3.b. The sequence r₁(n) is mapped to the alternate sub-carriers of the11^(th) OFDM symbol, starting from the lowest indexed or 2^(nd) lowestindexed sub-carrier of the lowest indexed RB, if O^((λ))(1)=0 orO^((λ))(1)=1, respectively, as illustrated in 904 and 905 of FIG. 9.

3.b.i. Alternatively, the sequence r₁(n) is mapped to the alternatesub-carriers of the 11^(th) OFDM symbol, starting from the highestindexed or 2^(nd) highest indexed sub-carrier of the highest indexed RB,if O^((λ))(1)=0 or O^((λ))(1)=1, respectively.

3.b.ii. Alternatively, the sequence r₁(n) is mapped to the alternatesub-carriers of the 11^(th) OFDM symbol, starting from the lowestindexed or 2^(nd) lowest indexed sub-carrier of the lowest indexed RB,if O^((λ))(1)=1 or O^((λ))(1)=0, respectively.

3.b.iii. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4^(th) OFDM symbol, starting from the highestindexed or 2^(nd) highest indexed sub-carrier of the highest indexed RB,if O^((λ))(1)=1 or O^((λ))(1)=0, respectively.

Alternate embodiments may be derived by replacing each occurrence of[O^((λ))(0) O^((λ))(1)]=[0 0] by [1 1] and each occurrence of[O^((λ))(0) O^((λ))(1)]=[1 1] by [0 0] in the last column of Table 2.

Embodiment Set 1.1.2

For this set of embodiments, as in Embodiment Set 1.1.1, the legacytable is extended by the addition of a column which defines, for eachvalue of the cyclic shift field and for the specific case of the numberof transmissions layers (λ+1)=1, two offset parameters, denoted by thesymbols O^((λ))(0) and O^((λ)) (1). The resulting table is illustratedin Table 3.

Table 3: Extension of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE

TABLE 3 Extension of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE Cyclic Shift Field in uplink-related DCIn⁽²⁾ _(DMRS, λ) [w^((λ))(0) w^((λ))(1)] [O^((λ))(0) O^((λ))(1)] format[3] λ = 0 λ = 1 λ = 2 λ = 3 λ = 0 λ = 1 λ = 2 λ = 3 λ = 0 000 0 6 3 9 [11] [1 1] [1 −1] [1 −1] [0 0] 001 6 0 9 3 [1 −1] [1 −1] [1 1] [1 1] [0 0]010 3 9 6 0 [1 −1] [1 −1] [1 1] [1 1] [0 0] 011 4 10 7 1 [1 1] [1 1] [11] [1 1] [1 1] 100 2 8 5 11 [1 1] [1 1] [1 1] [1 1] [1 1] 101 8 2 11 5[1 −1] [1 −1] [1 −1] [1 −1] [1 1] 110 10 4 1 7 [1 −1] [1 −1] [1 −1] [1−1] [1 1] 111 9 3 0 6 [1 1] [1 1] [1 −1] [1 −1] [0 0]

The added column has been highlighted at the right end in Table 3.

The motivation for this set of embodiments is similar to those ofEmbodiment Set 1.1.1. These embodiments disclose a technique to increasethe number of UEs whose DMRS sequences can be orthogonally separated viathe usage of a comb structure for the DMRS, whereby the DMRS ofdifferent UEs can occupy non-overlapping resources irrespective ofwhether the corresponding allocated PUSCH resources are overlapping ornon-overlapping. This is achieved by placing the DMRS sequence values atevery third sub-carrier of the DMRS symbols as illustrated in902/903/904/905 of FIG. 9, instead of at every sub-carrier of the DMRSsymbols as in the legacy design in REF 1. The offset parameter valuesO^((λ))(0) and O^((λ))(1), with (+1) denoting the number of layers,determine the starting sub-carrier for the DMRS sequence placement inthe DMRS symbols in Slot #s 0 and 1 of each RB in the allocation,respectively.

FIGS. 10, 11A, and 11B illustrate example UE operations with respect todetermining the uplink DMRS sequences to use and their positions in theallocated RBs according to the embodiments of the present disclosure.

1. Referring to FIG. 10, in step 1001, the eNB indicates the uplinkPUSCH transmission parameters to UE. These include the N contiguous RBswith indices S through (S+N−1), the parameter λ indicating the number oflayers as (λ+1), the cyclic shift field value v indexing each row ofTable 3, as well as other legacy parameters described in REF 1. In thisset of embodiments, λ=0 so that the number of indicated layers as(λ+1)=1.

2. In step 1002, the UE calculates the length of the up-link DMRSsequence as M_(SC) ^(RS)=M_(SC) ^(RB).N/3, where M_(SC) ^(RB)=12 is thenumber of sub-carriers per OFDM symbol per RB

3. In step 1003, the UE generates the DMRS sequence r(n), with n=0, . .. ,└M_(SC) ^(RS)┘−1, where └x┘ represents the floor value of theparameter x, using: 3.a The value of the n_(DMRS,λ) ⁽²⁾ parameterobtained from the row corresponding to the cyclic shift field value vand the λ=0 column of the set of columns corresponding to n_(DMRS,λ) ⁽²⁾the parameter; and 3.b The other legacy parameters indicated by the eNBin (1) above.

4. In step 1004, the UE generates the uplink DMRS sequencesr₀(n)=w^((λ)) (0).r(n) and r₁(n)=w^((λ))(1).r(n) using the values of thecover code parameters w^((λ))(0) and w^((λ))(1) corresponding to the vthrow and the λ=0 column of the set of columns corresponding to the[w^((λ))(0) w^((λ))(1)] parameters of Table 2.

In step 1005, the UE then maps the generated sequences r₀(n) and r₁(n)to the uplink OFDM symbol grid as shown in FIG. 11A. As in 1101, themapping rule is based on the offset parameters O^((λ))(0) andO^((λ))(1), as follows. These offset parameters are determined from therow corresponding to the cyclic shift field value v and the (′) columncorresponding to the O^((λ))(0) O^((λ))(1) parameters of Table 3.

1. As in FIG. 11A, each RB consists of 12 sub-carriers in frequency and14 OFDM symbols in time. The sequences r₀(n) and r₁(n) are mapped to thesub-carriers in the 4th and 11th OFDM symbol of each of the N RBs in theallocation, respectively.

2. The offset parameter O^((λ))(0) is used to map the sequence r₀(n) tothe 4th OFDM symbol of each of the N RBs in the allocation.

3. In one embodiment sub-set of this embodiment set, sub-carriers in anOFDM symbol are indexed sequentially, with adjacent sub-carriers beingassigned adjacent integer values. Further, sub-carrier indexing followsthe RB indexing such that if n_(Highest) is the highest sub-carrierindex in any OFDM symbol of an RB with a certain RB index R, then thelowest sub-carrier index in the next higher RB index (R+1) isn_(Highest)+1. Then:

3.a. The sequence r₀(n) is mapped to the alternate sub-carriers of the4th OFDM symbol, starting from the lowest indexed, 2nd lowest indexed or3rd lowest indexed sub-carrier of the lowest indexed RB, ifO^((λ))(0)=0, O^((λ))(0)=1 or O^((λ))(0)=2, respectively, as illustratedin 1102, 1103 and 1104 of FIG. 11A.

3.a.i. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4th OFDM symbol, starting from the highest indexed,2^(nd) highest or 3^(rd) highest indexed sub-carrier of the highestindexed RB, if O^((λ))(0)=0, O^((λ))(0)=1 or O^((λ))(0)=2, respectively.

3.a.ii. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4th OFDM symbol, starting from the lowest indexed,2nd lowest indexed or 3rd lowest indexed sub-carrier of the lowestindexed RB, if O^((λ))(0)=2, O^((λ))(0)=1 or O^((λ))(0)=0, respectively.

3.a.iii. Alternatively, the sequence r₀(n) is mapped to the alternatesub-carriers of the 4th OFDM symbol, starting from the highest indexedor 2nd highest indexed sub-carrier of the highest indexed RB, if, ifO^((λ))(0)=2, O^((λ))(0)=1 or O^((λ))(0)=0, respectively.

3.b. The sequence r₁(n) is mapped to the alternate sub-carriers of the11th OFDM symbol, starting from the lowest indexed, 2nd lowest indexedor 3rd lowest indexed sub-carrier of the lowest indexed RB, ifO^((λ))(0)=0, O^((λ))(0)=1 or O^((λ))(0)=2, respectively, as illustratedin 1105, 1106 and 1107 of FIG. 11B.

3.b.i. Alternatively, the sequence r₁(n) is mapped to the alternatesub-carriers of the 11th OFDM symbol, starting from the highest indexed,2nd highest or 3rd highest indexed sub-carrier of the highest indexedRB, if O^((λ))(0)=2, O^((λ))(0)=1 or O^((λ))(0)=0, respectively.

3.b.ii. Alternatively, the sequence r₁(n) is mapped to the alternatesub-carriers of the 11th OFDM symbol, starting from the lowest indexed,2nd lowest indexed or 3rd lowest indexed sub-carrier of the lowestindexed RB, if O^((λ))(0)=0, O^((λ))(0)=1 or O^((λ))(0)=2, respectively.

3.b.iii. Alternatively, the sequence r₁(n) is mapped to the alternatesub-carriers of the 11th OFDM symbol, starting from the highest indexedor 2nd highest indexed sub-carrier of the highest indexed RB, if, ifO^((λ))(0)=2, O^((λ))(0)=1 or O^((λ))(0)=0, respectively.

Alternate embodiments may be derived by the following changes to thelast column (the column defining the values of the [O^((λ))(0) O^((λ))(1)] parameters for the λ=0 case for various values of the cyclic shiftfield) of Table 3: (1) Replacing each occurrence of 0 by 1; (2)Replacing each occurrence of 0 by 2; (3) Replacing each occurrence of(1) by (2); and (4) Successive repetitions of (1), (2) and (3) above inany order.

Embodiment Set 2: Modifications to Existing Cyclic Shift and OCCIndication Table

This set of embodiments discloses techniques to allow the multiplexingof more than 2 UEs, each with possibly non-overlapping PUSCHallocations, by extending Table 1 by adding new parameters, while alsomodifying some of the mappings and interpretations of the existingparameters.

Embodiment Set 2.1: Support for Up-to 8 UE MU-MIMO with 1 Layer Per UE

This set of embodiments discloses techniques to enable the multiplexingof the UE DMRSs in the case that: up-to 8 UEs are allocated up-linkPUSCH transmissions in the same sub-frame; and each UE is allocated asingle PUSCH layer on the up-link.

The UE PUSCH allocations may be un-equal and partially-overlapping. Inan example situation, identifying two UEs, labeled as UE1 and UE2 fromout of the set of UEs with PUSCH allocations in a given sub-frame, UE1may be allocated a number N1 of contiguous RBs defined by starting andending RB indices S1 and E1 respectively, whereas UE2 may be allocated anumber N2 of contiguous RBs defined by starting and ending RB indices S2and E2 respectively, where N1, S1 and E1 may or may not equal N2, S2 andE2.

Since the following embodiment sub-sets disclose techniques applicableto the single-layer case, only the columns of the modified Table 1,corresponding to the single layer case and identified by the parametersetting 2=0, are shown in the tables in the embodiment sub-sets.

Embodiment Set 2.1.1

The indication table in this set of embodiments is shown in Table 4.

Table 4: Modification of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE

TABLE 4 Modification of existing indicatin table to support up-to 8 UEMU-MIMO with 1 layer per UE Cyclic Shift Field in uplink-related DCIn⁽²⁾ _(DMRS, λ) [w^((λ))(0) w^((λ))(1)] [O^((λ))(0) O^((λ))(1)] format[3] for λ = 0 for λ = 0 for λ = 0 000 0 [1 1] [0 0] 001 6 [1 1] [0 0]010 3 [1 −1] [0 0] 011 5 [1 −1] [1 1] 100 2 [1 1] [1 1] 101 8 [1 1] [11] 110 11 [1 −1] [1 1] 111 9 [1 −1] [0 0]

The UE operation with respect to determining the uplink DMRS sequencesto use and their positions in the allocated RBs is as described in FIGS.8 and 9 and the description about the UE operation with respect toEmbodiment Set 1.1.1, with “Table 2” being replaced by “Table 4” in theFIGURES/descriptions.

Embodiment Set 2.1.2

The indication table in this set of embodiments is shown in Table 5.

Table 5. Modification of existing indication table to support up-to 8 UEMU-MIMO with 1 layer per UE

TABLE 5 Modification of existing indicatin table to support up-to 8 UEMU-MIMO with 1 layer per UE Cyclic Shift Field in uplink-related DCIn⁽²⁾ _(DMRS, λ) [w^((λ))(0) w^((λ))(1)] [O^((λ))(0) O^((λ))(1)] format[3] for λ = 0 for λ = 0 for λ = 0 000 0 [1 1] [0 0] 001 6 [1 1] [0 0]010 3 [1 −1] [0 0] 011 5 [1 −1] [1 1] 100 2 [1 1] [1 1] 101 8 [1 1] [11] 110 11 [1 −1] [1 1] 111 9 [1 −1] [0 0]

The UE operation with respect to determining the uplink DMRS sequencesto use and their positions in the allocated RBs is as described in FIGS.8 and 9 and the description about the UE operation with respect toEmbodiment Set 1.1.1, with “Table 2” being replaced by “Table 5” in theFIGURES/descriptions.

The present disclosure also relates generally to wireless communicationsystems and, more specifically, to support signaling of quasi-colocationof antenna ports or beams for transmissions from user equipments (UEs)to a base station or for transmissions from a base station to UEs.Depending on the network type, the term “base station” or “BS” can referto any component (or collection of components) configured to providewireless access to a network, such as transmit point (TP),transmit-receive point (TRP), an enhanced base station (eNodeB or eNB),a macrocell, a femtocell, a WiFi access point (AP), or other wirelesslyenabled devices. Base stations may provide wireless access in accordancewith one or more wireless communication protocols, e.g., 5G 3GPP NewRadio Interface/Access (NR), long term evolution (LTE), LTE advanced(LTE-A), High Speed Packet Access (HSPA), Wi-Fi 802.11a/b/g/n/ac, etc.For the sake of convenience, the terms “BS” and “TRP” are usedinterchangeably in this patent document to refer to networkinfrastructure components that provide wireless access to remoteterminals. Also, depending on the network type, the term “userequipment” or “UE” can refer to any component such as “mobile station,”“subscriber station,” “remote terminal,” “wireless terminal,” “receivepoint,” or “user device.” For the sake of convenience, the terms “userequipment” and “UE” are used in this patent document to refer to remotewireless equipment that wirelessly accesses a BS, whether the UE is amobile device (such as a mobile telephone or smartphone) or is normallyconsidered a stationary device (such as a desktop computer or vendingmachine). A communication system includes a downlink (DL) that refers totransmissions from a base station or one or more transmission points toUEs and an uplink (UL) that refers to transmissions from UEs to a basestation or to one or more reception points.

To meet the demand for wireless data traffic having increased sincedeployment of 4G communication systems, efforts have been made todevelop an improved 5G or pre-5G communication system. Therefore, the 5Gor pre-5G communication system is also called a ‘Beyond 4G Network’ or a‘Post LTE System’. The 5G communication system is considered to beimplemented in higher frequency (mmWave) bands, e.g., 60 GHz bands, soas to accomplish higher data rates. To decrease propagation loss of theradio waves and increase the transmission distance, the beamforming,massive multiple-input multiple-output (MIMO), Full Dimensional MIMO(FD-MIMO), array antenna, an analog beam forming, large scale antennatechniques are discussed in 5G communication systems. In addition, in 5Gcommunication systems, development for system network improvement isunder way based on advanced small cells, cloud Radio Access Networks(RANs), ultra-dense networks, device-to-device (D2D) communication,wireless backhaul, moving network, cooperative communication,Coordinated Multi-Points (CoMP), reception-end interference cancellationand the like.

For a communication system such as Long Term Evolution (LTE), signalingto indicate quasi co-location of antenna ports was introduced in orderto improve the quality of channel estimation based on demodulation RS(DMRS) and PDSCH reception. In LTE, two antenna ports are said to bequasi co-located if the large-scale properties of the channel over whicha symbol on one antenna port is conveyed can be inferred from thechannel over which a symbol on the other antenna port is conveyed. Thelarge-scale properties include one or more of delay spread, Dopplerspread, Doppler shift, average gain, and average delay.

Two types of QCL of antenna ports for PDSCH (antenna port 7-14) aredefined in LTE. Type A: The UE may assume the antenna ports 0-3 (CRSports), 7-30 (DM-RS ports and CSI-RS ports) of a serving cell are quasico-located with respect to delay spread, Doppler spread, Doppler shift,and average delay. Type B: The UE may assume the antenna ports 15-30(CSI-RS ports) corresponding to the CSI-RS resource configurationconfigured by the higher layers and the antenna ports 7-14 (DM-RS ports)associated with the PDSCH are quasi co-located with respect to Dopplershift, Doppler spread, average delay, and delay spread.

Type A QCL is beneficial for supporting communications withouttransmission from multiple points to the same UE, while Type B QCL isbeneficial for communications with coordinated multiple-point (CoMP)transmissions, such as dynamic point selection (DPS).

To enable dynamic indication of quasi co-location information in LTE, aUE configured in transmission mode 10 for a given serving cell can beconfigured with up to 4 parameter sets by higher layer signaling todecode PDSCH according to a detected PDCCH/EPDCCH with DCI format 2Dintended for the UE and the given serving cell. The UE shall use theparameter set according to the value of the ‘PDSCH RE Mapping andQuasi-Co-Location indicator’ field in the detected PDCCH/EPDCCH with DCIformat 2D for determining the PDSCH RE mapping, and for determiningPDSCH antenna port quasi co-location if the UE is configured with Type Bquasi co-location type. The parameter set comprises of quasi co-locatedCRS information (with respect to Doppler shift, and Doppler spread), thequasi co-located CSI-RS configurations and the starting OFDM symbol forPDSCH and the MBSFN subframe configuration.

Rel.13 LTE supports up to 16 CSI-RS antenna ports which enable an eNB tobe equipped with a large number of antenna elements (such as 64 or 128).In this case, a plurality of antenna elements is mapped onto one CSI-RSport. Furthermore, up to 32 CSI-RS ports will be supported in Rel.14LTE. For next generation cellular systems such as 5G, it is expectedthat the maximum number of CSI-RS ports remain more or less the same.

FIG. 12 illustrates an example transceiver 1200 comprising a largenumber of antenna elements according to embodiments of the presentdisclosure.

For mmWave bands, although the number of antenna elements can be largerfor a given form factor, the number of CSI-RS ports—which can correspondto the number of digitally precoded ports—tends to be limited due tohardware constraints (such as the feasibility to install a large numberof ADCs/DACs at mmWave frequencies) as illustrated in FIG. 12.

In this case, one CSI-RS port is mapped onto a large number of antennaelements which can be controlled by a bank of analog phase shifters1201. One CSI-RS port can then correspond to one sub-array whichproduces a narrow analog beam through analog beamforming 1205. Thisanalog beam can be configured to sweep across a wider range of angles(1220) by varying the phase shifter bank across symbols or subframes.The number of sub-arrays (equal to the number of RF chains) is the sameas the number of CSI-RS ports NCSI-PORT. A digital beamforming unit 1210performs a linear combination across NCSI-PORT analog beams to furtherincrease precoding gain. While analog beams are wideband (hence notfrequency-selective), digital precoding can be varied across frequencysub-bands or resource blocks.

The present disclosure addresses a need to specify a new antennaports/beams quasi co-location framework and the corresponding signallingmethods for 5G or NR communication systems.

For 5G or NR communication systems, a new reference signal (RS) can bedefined to support beam-based operations such as the hybrid beamformingoperation as shown in FIG. 12 at mmWave bands or FD-MIMO or massive MIMOoperations for lower frequency bands. The functionalities supported bythe new RS can include synchronization with a beam (or a composite beam)with the serving base station(s), measurement of a beam (or a compositebeam) transmitted by the serving base station(s), reference forestimating large-scale channel properties (such as one or more of delayspread, Doppler spread, Doppler shift, average gain, and average delay)or direct channel estimation reference for the purpose of demodulationof one or more physical channels, and reference for CSI feedback. ForNR, one or more new large scale channel properties can also be defined,such as ‘channel blockage’ (other possible name is ‘short term averageagain’, ‘small scale channel again’ and the like). The introduction ofnew large scale channel properties can be carrier frequency dependent.For example, ‘channel blockage’ is included as part of the large scalechannel properties for carrier frequency above X GHz. The new RS shallbe referred to as measurement RS (MRS). Other names are possible such asbeam RS (BRS) (for beam-formed system), or CSI-RS. A single TRP cantransmit multiple MRSs. The MRSs from a single TRP may or may not havethe same coverage. A UE may be configured to receive MRS from a singleTRP or from multiple TRPs in a CoMP operation.

A 5G communication system can be configured with cell-specific MRS(where the configuration of MRS and/or its transmission (or UEassumption of transmission) is the same for all UEs served by the samecell) or UE-specific MRS (where the configuration of MRS and/or itstransmission (or UE assumption of transmission) is UE-specific). A MRScan be mapped to only one OFDM symbol in a subframe or multiple OFDMsymbols in a subframe.

FIG. 13 illustrates an example construction of MRS antenna ports,configurations and configuration groups according to some embodiments ofthe present disclosure.

In one method, a set of MRS antenna ports (MRS AP 0, . . . , N_(AP)−1)corresponds to a beam. Such set of MRS antenna ports is referred to asan MRS configuration, or an MRS resource. One or more MRS configurations(one or more beams) can be grouped into one or more groups (beamgroups). Such group of MRS configurations is referred to as an MRSconfiguration group, or an MRS resource set or setting.

FIG. 14A illustrates another example construction of MRS antenna ports,configurations and configuration groups, where the MRS configurationsand grouping are based on the beam IDs according to the embodiments ofthe present disclosure.

Each MRS configuration corresponds to a set of beam IDs. For example,MRS configuration 1 corresponds to beam IDs a_1, . . . a_Na; and MRSconfiguration N_(MRS) corresponds to beam IDs x_1, . . . , x_Nx.Multiple MRS configurations correspond to an MRS configuration group,and the total number of beam IDs for an MRS configuration group isN_(AP)·N_(MRS). This is illustrated in FIG. 14A.

For this method, unique beam IDs are allocated to MRS mapped on the OFDMsymbols in a time period. N_(AP)·N_(MRS) belonging to an MRSconfiguration group are mapped onto N_(MRS) OFDM symbols, each of whichhas REs to map reference signals for N_(AP) different beams. In someembodiments, the unique beam IDs may be referred to as MRS antenna portnumbers; in this case the MRS antenna port numbers will be 0, . . .N_(AP) N_(MRS)−1 and the total number of MRS ports is N_(AP)·N_(MRS). Inthis disclosure, MRS antenna ports may refer to beam IDs, and those twoterminologies can be used inter-changeably.

In some embodiments, the number of beams in an MRS configuration groupis configured in initial access broadcast signaling.

In some embodiments, UE is configured with multiple MRS configurationgroups (e.g., for inter-cell CoMP), and the numbers of beams for theconfigured MRS configuration groups are RRC configured.

QCL Definition for MRS

FIG. 14B illustrates an example QCL definition for MRS according toembodiments of the present disclosure.

In the first alternative as shown in FIG. 14B, if two MRS antenna portsbelong to the same MRS configurations group at block 1405, the MRSantenna ports belonging to the same MRS configuration group are quasico-located in one or more of the large scale channel properties,regardless of whether the MRS antenna ports belong to the same MRSconfiguration or different MRS configurations at block 1410. In otherwords, the large scale channel parameters estimated using the MRSantenna ports belonging to the same MRS configuration are highlycorrelated. The UE may assume that the MRS antenna ports belonging tothe same group are quasi co-located. Otherwise, the MRS antenna portsare not quasi co-located with respect to a predefined or configured setof large scale channel properties at block 1415.

FIG. 14C illustrates another example QCL definition for MRS according toembodiments of the present disclosure.

In the second alternative as shown in FIG. 14C, the large scale channelproperties involved in the quasi co-location assumption for two MRSantenna ports can be assumed as a function of their MRS configurationassociation and their MRS configurations group association. If two MRSantenna ports belong to the same MRS configuration at block 1430, thenthe MRS antenna ports are quasi co-located with respect to a first setof large scale channel properties (the UE may assume that the MRSantenna ports are quasi co-located with respect to the first set oflarge scale channel properties) at block 1435; else if the MRS antennaports belong to the same MRS configurations group at block 1440, thenthe MRS antenna ports are quasi co-located with respect to a second setof large scale channel properties (the UE may assume that the MRSantenna ports are quasi co-located with respect to the second set oflarge scale channel properties) at block 1445; else the MRS antennaports are not quasi co-located with respect to the predefined (orconfigured) large scale channel properties (the UE may not assume thatthe MRS antenna ports are quasi co-located) at block 1455.

An example of the first set of large scale channel properties is {delayspread, Doppler spread, Doppler shift, average gain, and average delay}.An example of the second set of large scale channel properties is(Doppler spread, Doppler shift).

The first and the set sets of large scale channel properties can beeither predefined or can be configured by the network (e.g. by RRCsignaling). An advantage of network configuration of the large scalechannel properties to be included in each set is that it can enableflexible use of the QCL framework depending on the deployment scenario.

In a third alternative, whether the UE assumes the first or the secondalternative can be configured by the network (e.g. by RRC signaling).The first alternative can be seen as a special case of the secondalternative where the first and the second set of large scale channelproperties are the same. The first or the second set of large scalechannel properties can also be configured to be an empty set. Forexample, if the second set is configured to be an empty set, it impliesthat the UE may not assumed the MRS antenna ports belonging to differentMRS configurations to be quasi co-located, regardless of the grouping.

The MRS configurations and the MRS configurations groups can be signaledto the UE by the network, e.g. by the higher layers. In addition, thelarge scale channel properties applied for QCL relationship for antennaports within a configuration or within a configurations group can besignaled to the UE by the network, e.g. by the higher layers. The higherlayer signaling can be RRC signaling in a UE-specific manner, or it canbe broadcast to UEs in a common broadcast control channel, such as a MIBor a SIB. A configuration ID can be associated with a configuration anda configurations group ID can be associated with a configurations group.Any two MRS antenna ports belong to the same MRS configuration if theyare associated with the same configuration ID; otherwise they belong todifferent MRS configurations. Any two MRS antenna ports belong to thesame MRS configurations group if their respective MRS configuration isassociated with the same MRS configurations group ID; otherwise theybelong to different MRS configurations groups.

An advantage of the framework described above is that it can enable thenetwork to flexibly configure MRS configurations and MRS configurationgroups according to the deployment scenario, including scenarios withbeamforming-based system and non-beamforming based systems (ormulti-beam based systems and single-beam based systems).

Denote N_(G) as the number of MRS configurations groups, N_(B) as thenumber of MRS configurations within a group (which is assumed the samefor all groups for simplicity. In general N_(B) can be different fordifferent group), and N_(P) as the number of MRS antenna ports within anMRS configuration (assumed the same for all configurations forsimplicity). These numbers can be higher-layer configured. The followingare some example network configurations:

Example 1: For non-CoMP deployment scenario in a sub-6 GHz band(excluding FD-MIMO class B with the number of precoded CSI-RS, K>1), thenetwork can configure N_(G)=1, N_(B)3=1, N_(P)=1, 2, 4, 8, 16, 32, . . .

Example 2: For non-CoMP FD-MIMO class B with K>1 at sub-6 GHz band, thenetwork can configure N_(G)=1, N_(B)=K, N_(P)=1, 2, 4, 8, 16, 32, . . ..

Example 3: For CoMP deployment at sub-6 GHz band, assuming CoMPoperation with X TRPs, where each TRP is equipped with N_(P) antennaports, the network can configure N_(G)=X, N_(B)=1, N_(P)=1, 2, 4, 8. Tosupport a CoMP DPS operation, the first set of large scale channelproperties can be configured to be (delay spread, Doppler spread,Doppler shift, average gain, and average delay), while the second set oflarge scale channel properties can be configured to be (Doppler spread,Doppler shift) if frequency offset between TRPs is sufficiently small,or an empty set if the UE is required to estimate the frequency offsetof each TRP separately. To support a CoMP non-coherent JT operation, thefirst set of large scale channel properties can be configured to be(delay spread, Doppler spread, Doppler shift, average gain, and averagedelay), while the second set of large scale channel properties can beconfigured to be (Doppler spread, Doppler shift). To support a CoMPcoherent JT operation, the first set and the second set of large scalechannel properties can be configured to be (delay spread, Dopplerspread, Doppler shift, average gain, and average delay).

Example 4: For Non-CoMP deployment at above-6 GHz bands (mmWave bands)where a TRP is equipped with X lowly correlated beam groups (not QCL-edin “channel blockage”) with Y highly correlated beams per group (QCL-edin “channel blockage”), the network can configure N_(G)=X, N_(B)=Y,N_(P)=1, 2, 4, 8. Configuring multiple groups for non-CoMP scenario isbeneficial for protection against random channel blockage phenomenon atmmWave bands, as this can enable the network to switch the beam group toserve a UE when the current serving beam group suffers from blockage.

Example 5: For CoMP deployment at above-6 GHz bands (mmWave bands) withX TRP where each TRP is configured with Y beams, the network canconfigure N_(G)=X, N_(B)=Y, N_(P)=1, 2, 4, 8.

QCL Relationships Between MRS and Other RSs

In addition to QCL relationships between MRS antenna ports, there is aneed to specify the QCL relationships between MRS antenna ports and theother RS types. The relationships can be different depending on whetherthe MRS is a cell-specific signal or a UE-specific signal. In thisdisclosure, the DM-RS for PDSCH is used as the example RS. It isunderstood that the principles can be extended to the DM-RS for otherphysical channels such as PDCCH. The following QCL types are possible.In the QCL types devised below, MRS may refer to one of MRS antennaport(s) in a configuration group, MRS configuration(s), or MRSconfiguration group(s). In a special case, cell-specific MRS may bereferred to as BRS; and UE-specific MRS may be referred to BRRS orCSI-RS.

Type 0: PDSCH DM-RS is “self-contained” in terms of QCL properties, i.e.the PDSCH DM-RS is not quasi co-located with other RS types with respectto a predefined or configured set of large scale channel properties.Type 0 can be applied for a certain deployment scenario or for a certainPDSCH DM-RS design. For example, Type 0 is applied when the DM-RS andthe PDSCH is transmitted with a sufficiently narrow beam, and when theDoppler shift and Doppler spread is sufficiently small. In anotherexample, Type 0 can be applied when the PDSCH DM-RS is designed to havesufficient density in frequency and time.

Type 1: A cell-specific MRS is quasi co-located with PDSCH DM-RS withrespect to a predefined or configured set of large scale channelproperties. An example of the cell-specific MRS is a cell-specific BRS.An example of the large scale channel properties is {average gain, andaverage delay, delay spread, Doppler spread and Doppler shift}. A cellmay have multiple cell-specific MRS identified by a distinct MRSconfigurations group. In this case, Type 1 can be applied tocell-specific MRS from a group, i.e. a cell-specific MRS belonging to agroup is quasi co-located with PDSCH DM-RS.

Type 1 is applicable e.g. when the cell-specific MRS has sufficienttime-domain density for Doppler estimation, or when the channel hassufficiently small Doppler, and when the DM-RS precoding is formed onthe same set of beams comprising the cell-specific MRS.

Type 2: A cell-specific MRS is quasi co-located with PDSCH DM-RS withrespect to a first set of large scale channel properties while aUE-specific MRS is quasi co-located with PDSCH DM-RS with respect to asecond set of large scale channel properties. The set of cell-specificMRS and the set of UE-specific MRS that are quasi-located with PDSCHDM-RS in their respective large scale channel properties can beconfigured by the network, e.g. by higher layer signaling.

For example, the MRS configurations indicated can include (but notlimited to) the number of antenna ports, the ID used for scrambling theMRS or for identifying the resource location of the MRS (in time andfrequency), the bandwidth of the MRS and the actual set of large scalechannel properties for quasi co-location assumption with the PDSCHDM-RS. When more than one UE-specific MRS configurations which are notquasi co-located (e.g. because they belong to different group) can bequasi co-located with PDSCH DM-RS, the UE-specific MRS configurationthat may be assumed by the UE to be quasi co-located when receiving aPDSCH can be dynamically indicated in a PDCCH (chosen from the higherlayer configured set) e.g. the DCI scheduling the PDSCH (e.g. onsubframe or TTI basis). Moreover, when the second set of large scalechannel properties can be different for different set of UE-specificMRS, the set of large scale channel properties the UE may assume forquasi co-location is also dynamically changed according to DCI signaling(e.g. on subframe or TTI basis).

In one example of Type 2, or Type 2A, the first set of large scalechannel properties can be predefined or configured by the network to be(Doppler spread and Doppler shift), while the second set of large scalechannel properties can be refined or configured by the network to be(average gain, and average delay, delay spread). Type 2A is applicablee.g. for a CoMP deployment scenario where the cell-specific MRS istransmitted in a SFN manner while the UE-specific MRS is transmitted ina TRP-specific manner (in the same way as the PDSCH); and/or when thecell-specific MRS can provide sufficient quality of Doppler estimation(e.g. it has sufficient time domain density); and/or when the channelfor PDSCH has sufficiently small Doppler.

In another example of Type 2, or Type 2B, the first set of large scalechannel properties can be predefined or configured by the network to be(average gain, and average delay, delay spread), while the second set oflarge scale channel properties can be predefined or configured by thenetwork to be (Doppler spread and Doppler shift). Type 2B is applicablewhen the cell-specific MRS does not have sufficient time-domain densityfor Doppler estimation but UE-specific MRS has (or is configured tohave) sufficient time-domain density for Doppler estimation. An exampleof the cell-specific MRS is a cell-specific BRS. Examples of theUE-specific MRS includes a beam RS designed for fine beam alignment(beam refinement RS or BRRS) and CSI-RS.

Type 3: A UE-specific MRS is quasi co-located with PDSCH DM-RS withrespect to a predefined or configured set of large scale channelproperties. Examples of the UE-specific MRS includes BRRS and CSI-RS.The set of UE-specific MRS that are quasi-located with PDSCH DM-RS intheir respective large scale channel properties can be configured by thenetwork, e.g. by higher layer signaling. When more than one UE-specificMRS configurations which are not quasi co-located (e.g. because theybelong to different groups) can be quasi co-located with PDSCH DM-RS,the UE-specific MRS configuration that may be assumed by the UE to bequasi co-located when receiving a PDSCH can be dynamically indicated ina PDCCH e.g. the DCI scheduling the PDSCH (e.g. on subframe or TTIbasis). Moreover, when the second set of large scale channel propertiescan be different for different set of UE-specific MRS, the set of largescale channel properties the UE may assume for quasi co-location is alsodynamically changed according to DCI signaling (e.g. on subframe or TTIbasis).

The QCL types as described above can be configured by the network. Thisis beneficial when more than one RS pattern (which has differenttime-domain and/or frequency domain density) for MRS and/or DM-RS, andthe actual RS patterns to be assumed by the UE, can be configured by thenetwork. The QCL types can also be predefined or configured separatelyaccording the RS types or the corresponding physical channel or thetransport channel that are involved in the QCL relationship with theMRS. For example, the QCL relationship between PDCCH DM-RS and MRS canbe predefined or configured to be Type 0 (because of the low data rateand robust MCS of PDCCH) while the QCL relationship between PDSCH DM-RSand MRS can be predefined or configured to be Type 0, 1, 2, or 3. Inanother example, the DM-RS for PDSCH used for broadcast control channel(e.g. SIB) can be predefined or configured to be Type 0 while the DM-RSfor PDSCH used for unicast data can be predefined or configured to beType 0, 1, 2 or 3.

MRS Pattern Configurations and Relationships to QCL

In order to support scenarios that involve diverse mobility, delayspread etc., it may be beneficial to flexibly configure MRS pattern ordensity so that a desired subset of quasi-colocation properties {averagegain, and average delay, delay spread, Doppler spread and Doppler shift}may be estimated reliably.

In a first embodiment, cell-specific or UE-specific MRS pattern isassociated with QCL type configuration.

FIG. 15 illustrates an example MRS pattern configurations andrelationships to QCL, where the cell-specific or UE-specific MRS patternis associated with QCL type configuration according to embodiments ofthe present disclosure.

The UE derives the MRS patterns from the QCL type configurationssignaled to the UE (which can be directly signaled by the network or canbe derived through association via grouping with another MRS which isindicated the QCL type).

In the first example, when Type 1 QCL is configured for a cell-specificMRS such that PDSCH DM-RS is quasi co-located with the configured MRS onlarge scale channel properties (average gain, and average delay, delayspread, Doppler spread and Doppler shift) at block 1505, the MRS isconfigured with a first RS pattern whose time and frequency densityenables sufficient estimation of the large scale channel properties upto a certain propagation conditions, including (but not limited to)average gain, and average delay, delay spread, Doppler spread andDoppler shift at block 1510.

In the second example, when Type 1 QCL is configured for a cell-specificMRS such that PDSCH DM-RS is quasi co-located with the configured MRS onlarge scale channel properties {average gain, and average delay, delayspread}, the MRS is configured with a second RS pattern whose time andfrequency density enables sufficient estimation of the large scalechannel properties up to a certain propagation conditions, including(but not limited to) average gain, and average delay, delay spread.

In the third example, when Type 1 QCL is configured for a cell-specificMRS such that PDSCH DM-RS is quasi co-located with the configured MRS onlarge scale channel properties (Doppler spread and Doppler shift), theMRS is configured with a third RS pattern whose time and frequencydensity enables sufficient estimation of the large scale channelproperties up to a certain propagation conditions, including (but notlimited to) Doppler spread and Doppler shift.

In the fourth example, when Type 2 QCL is configured, such that acell-specific MRS is quasi co-located with PDSCH DM-RS with respect to afirst set of large scale channel properties while a UE-specific MRS isquasi co-located with PDSCH DM-RS with respect to a second set of largescale channel properties, the cell-specific MRS pattern isderived/determined from the respective set of large scale channelproperties.

In the fifth example, when Type 2 QCL is configured such that acell-specific MRS quasi co-located with PDSCH DM-RS with respect to afirst set of large scale channel properties while a UE-specific MRS isquasi co-located with PDSCH DM-RS with respect to a second set of largescale channel properties, then the cell-specific MRS pattern isderived/determined according to the first set of quasi co-locationproperties while the UE-specific MRS pattern is derived/determinedaccording to the combination of the first and the second set of quasico-location properties.

In the sixth example, when Type 3 QCL is configured such that aUE-specific MRS is configured to be quasi co-located with PDSCH DM-RS ona first set of large scale channel properties, the MRS pattern can bederived/determined from configured the quasi co-located large scalechannel properties.

In the second embodiment, a QCL type of configuration is associated witha cell-specific MRS pattern or a UE-specific MRS pattern.

FIG. 16A illustrates an example MRS pattern configurations andrelationships to QCL where a QCL type of configuration is associatedwith a cell-specific MRS pattern or a UE-specific MRS pattern accordingto embodiments of the present disclosure.

The UE is signaled an MRS pattern for an MRS at block 1605 and the UEderives/determines the QCL type and/or the set of quasi co-located largescale channel properties from the configured cell-specific MRS patternor the UE-specific MRS pattern or both at block 1615.

In another alternative, the UE derives or determines the set of quasico-located large scale channel properties from the configuredcell-specific MRS pattern or the UE-specific MRS pattern or both, aswell as the QCL type (without explicit configuration of the quasico-located large scale channel properties).

FIG. 16B illustrates an example MRS pattern configurations andrelationships to QCL according to embodiments of the present disclosure.

The UE is signaled an MRS pattern for an MRS and the QCL type at block1620, the UE derives or determines the set of quasi co-located largescale channel properties from the configured cell-specific MRS patternor the UE-specific MRS pattern or both, as well as the QCL type at block1625.

The rationale is that the large scale channel properties can beestimated depend on the MRS pattern (e.g., density in time andfrequency), and therefore given a configured MRS pattern, it can beassociated with the appropriate QCL assumptions.

In the first example, when the Type 1 QCL cell-specific MRS and a firstcell-specific MRS pattern are configured, a cell-specific MRS QCLconfiguration may be derived from the MRS pattern configuration. Underthis MRS pattern configuration, the QCL configuration indicates PDSCHDM-RS is quasi co-located with the configured MRS on a set of largescale channel properties.

In the second example, when the Type 2 QCL, with a cell-specific MRS ofcellMrsPattern pattern and a UE-specific MRS of ueMrsPattern pattern areconfigured, the cell-specific MRS is determined by the UE to be quasico-located with a first set of large scale channel properties and theUE-specific MRS is determined to be quasi co-located with a second setof large scale channel properties.

In the third example, when the Type 3 QCL, K+1 (K>=0) UE-specific MRSsare configured patterns {ueMrsPattern0 . . . ueMrsPatternK}. A QCLconfiguration can be derived from the pattern configuration configuredfor each UE-specific MRS, and is assumed to be quasi co-located with asame or different set of large scale channel properties.

In the third embodiment, a cell-specific MRS pattern or a UE-specificMRS pattern or both are configured independently regardless of QCL typeor configuration for the MRS.

In the first example, a certain cell-specific MRS pattern is configuredwhere the pattern corresponds to a certain type of time and frequencyallocation for the MRS. The pattern can be indicated by bit field thatmay be dynamically signaled by DCI or semi-statically configured byhigher layer signaling.

In the second example, one or more UE-specific MRS pattern(s) areconfigured, each pattern corresponding to a group of MRS. For example,two UE-specific MRS patterns are configured, where a first set ofconfigured UE-specific MRS has the first MRS pattern and a second set ofconfigured UE-specific MRS has the second MRS pattern. Indications ofwhich UE-specific MRS belong to the first set and which belong to thesecond set may be signaled by bit field either by DCI or higher layersignaling. For example, “0” implies an MRS is associated with the firstset of MRS pattern and “1” implies the MRS is associated with the secondset of MRS pattern.

In the third example, a certain cell-specific MRS pattern is configuredtogether with one or more UE-specific MRS pattern(s). In one example, ajoint bit field may be used to jointly configure one cell-specific MRSpattern and one UE-specific pattern: “0” may correspond to a first setof configurations including a cell-specific MRS pattern and aUE-specific MRS pattern, and “1” may correspond to a second set ofconfiguration including a same or different cell-specific MRS patternand UE-specific MRS pattern.

UE Initiated or Requested MRS Configurations

One purpose of QCL is for a UE to associate large scale channelproperties for improving channel estimation quality. Due to varying UEcapabilities, dynamically changing UE propagation conditions as well asdifferent quality-of-service (QoS), an UE may need different support ofQCL during its channel estimation. Therefore, it may be advantageous fora UE to request the network to configure MRS according to its needs.

In the first embodiment, a UE is configured with K cell-specific MRSpatterns and/or N UE-specific MRS patterns. The UE is served by a subsetof the configured cell-specific patterns and/or UE specific patterns,and the UE can request a change of cell-specific MRS pattern and/orUE-specific MRS pattern to the network.

In the first example, when the QCL Type 3 is configured to be quasico-located on large scale channel properties {average gain, and averagedelay, delay spread, Doppler spread and Doppler shift} and anUE-specific MRS is transmitted on a certain MRS pattern out of NUE-specific MRS patterns. The TIE may request a change of MRS patternvia a bit field indication on either PUCCH or PUSCH or RACH.

Alternatively, UE request can be performed via higher layering signalingsuch as MAC CE signaling or RRC signaling. For example, assuming Xnumber of possible RS patterns are predefined or configured by thenetwork via higher layer signaling (e.g. RRC), log₂(λ) bits can beincluded in a PUCCH format or in the UCI payload for PUSCH to requestfor one of the X RS patterns.

In another alternative, the UE indicates e.g. with 1 bit, the request tochange MRS pattern, without indicating the desired MRS pattern and it isup to the network to configure the updated MRS pattern. Conditions totrigger change request may depend on UE implementation and may relate tochanges of UE propagation conditions such as UE speed, delay spread orblockage. For example, the current serving UE-specific MRS pattern maysupport to up to a certain speed, and the UE speed may increase and theUE may detect that the time-density of the current UE-specific MRSpattern is insufficient. Therefore, the UE may trigger to change toUE-specific MRS pattern with higher time density.

In another alternative, the UE triggers a request to change MRS patternif a predefined or configured condition is satisfied. In one example,HARQ-NACK has been generated or reported for a certain number of times(predefined or configured). In another example, the condition is thatthe UE measured delay spread or Doppler has exceeded a certainthreshold.

In the second example, when the QCL Type 2 is configured where acell-specific MRS is quasi co-located with PDSCH DM-RS with respect to afirst set of large scale channel properties, while a UE specific MRS isquasi co-located with PDSCH DM-RS with respect to a second set of largescale channel properties. The UE-specific MRS is transmitted accordingto a certain UE-specific MRS pattern out of K UE-specific MRS patterns.The UE may request a change of UE-specific MRS pattern without changingthe cell-specific MRS pattern.

Additional signaling methods to support non-coherent joint transmission(JT)

For enabling non-coherent JT transmission, the DM-RS ports of differentset of data (PDSCH) transmission layers can be configured to be quasico-located with different set of UE-specific MRS antenna ports (eitherMRS configuration or configurations group). For example, assumingnon-coherent JT from two TRPs, the DM-RS ports of a first of set of data(PDSCH) transmission layers (from a first TRP) can be configured to bequasi co-located with a first set of UE-specific MRS antenna ports,while the DM-RS ports of a second set of data (PDSCH) transmissionlayers (from a second TRP) can be configured to be quasi co-located witha second set of UE-specific MRS antenna ports. The set of UE-specificMRS configurations for non-coherent JT operation can be configured tothe UE by the network by higher layer signaling. There is a need tospecify the QCL mapping of PDSCH layers to UE-specific MRSconfigurations.

In one method, the QCL association of a set of PDSCH layers with an MRSconfiguration can be signaled explicitly in a PDCCH, e.g. the PDCCHcontaining the DCI scheduling the corresponding PDSCH. Assuming XUE-specific MRS configurations are configured with quasi co-locationwith PDSCH DMRS, log₂(λ) number of bits can be included in the DCIscheduling a set of PDSCH layers to indicate one of the X quasico-located UE-specific MRS. The information bits can also be jointlyencoded with other information field.

In another method, the QCL association of a set of PDSCH layers with anMRS configuration can be signaled implicitly with other information ofthe PDSCH layers or attributes associated with the PDSCH layers. Forexample, assuming the PDSCH layers of a TRP corresponds to one codeword,then the codeword index for the PDSCH layers can be used to map to a setof UE-specific MRS antenna ports for QCL assumption purpose (e.g. thePDSCH layers corresponding to a first codeword is assumed quasico-located with a first set of MRS antenna ports, while the PDSCH layerscorresponding to a second codeword is assumed quasi co-located with asecond set of MRS antenna ports). The codeword index can be explicitlyobtained from the DCI or can be implicitly derived, e.g. if codewordindex is used to scramble the PDCCH or the PDCCH's CRC. Instead ofcodeword index, other possible examples include HARQ process ID(assuming the PDSCH layers of a TRP corresponds to one HARQ process ID),TRP ID (or virtual cell ID) (assuming the PDSCH layers of a TRP can beidentified with the TRP ID).

To aid the Patent Office and any readers of any patent issued on thisapplication in interpreting the claims appended hereto, applicants wishto note that they do not intend any of the appended claims or claimelements to invoke 35 U.S.C. § 112(f) unless the words “means for” or“step for” are explicitly used in the particular claim. Use of any otherterm, including without limitation “mechanism,” “module,” “device,”“unit,” “component,” “element,” “member,” “apparatus,” “machine,”“system,” “processor,” or “controller,” within a claim is understood bythe applicants to refer to structures known to those skilled in therelevant art and is not intended to invoke 35 U.S.C. § 112(f).

Although the present disclosure has been described with an exampleembodiment, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

What is claimed:
 1. A base station, comprising: at least onetransceiver; and at least one processor configured to: transmitconfiguration information for sets of large scale channel properties toa user equipment (UE) via the at least one transceiver, wherein a typeof each of the sets of large scale channel properties is one of aplurality of types including a first type and a second type, wherein, ifthe type is the first type, the set of large scale channel propertiescomprises a delay spread, a Doppler spread, a Doppler shift, and anaverage delay, and wherein, if the type is the second type, the set oflarge scale channel properties comprises a Doppler spread and a Dopplershift, and transmit a demodulation reference signal (DM-RS) of aphysical downlink shared channel (PDSCH) to the UE via the at least onetransceiver, wherein an antenna port of the DM-RS of the PDSCH and anantenna port of a first reference signal (RS) are quasi co-locatedaccording to a first of the sets of large scale channel properties andthe antenna port of the DM-RS of the PDSCH and an antenna port of asecond RS are quasi co-located according to a second of the sets oflarge scale channel properties.
 2. The base station of claim 1, whereinthe sets of large scale channel properties each include at least one ofa delay spread, a Doppler spread, a Doppler shift, an average gain, oran average delay, and wherein the configuration information istransmitted via a radio resource control (RRC) signaling.
 3. The basestation of claim 1, wherein the first set of large scale channelproperties is associated with an RS configuration corresponding to thefirst RS, and wherein the RS configuration indicates a RS pattern forthe first RS.
 4. The base station of claim 3, wherein the RSconfiguration includes a number of antenna ports and a scramblingidentity.
 5. The base station of claim 3, wherein RS ports of the RSconfiguration are quasi co-located according to large scale channelproperties including a delay spread, a Doppler spread, a Doppler shift,an average gain, and an average delay.
 6. The base station of claim 3,wherein the RS pattern corresponds to a type of time and frequencyallocation for one or more RSs of the RS configuration.
 7. The basestation of claim 1, wherein a RS pattern of the first RS is configuredby higher layer signaling, and wherein the first RS comprises a channelstate information-reference signal (CSI-RS).
 8. The base station ofclaim 1, wherein the at least one processor is further configured to:transmit downlink control information (DCI) including bits on a physicaldownlink control channel (PDCCH) to the UE via the at least onetransceiver, wherein the bits indicate a RS configuration among RSconfigurations specific to the UE and one of the sets of large scalechannel properties.
 9. A user equipment (UE), comprising: at least onetransceiver; and at least one processor configured to: receiveconfiguration information for sets of large scale channel propertiesfrom a base station via the at least one transceiver, wherein a type ofeach of the sets of large scale channel properties is one of a pluralityof types including a first type and a second type, wherein, if the typeis the first type, the set of large scale channel properties comprises adelay spread, a Doppler spread, a Doppler shift, and an average delay,and wherein, if the type is the second type, the set of large scalechannel properties comprises a Doppler spread and a Doppler shift, andreceive a demodulation reference signal (DM-RS) of a physical downlinkshared channel (PDSCH) from the base station via the at least onetransceiver, wherein an antenna port of the DM-RS of the PDSCH and anantenna port of a first reference signal (RS) are quasi co-locatedaccording to a first of the sets of large scale channel properties andthe antenna port of the DM-RS of the PDSCH and an antenna port of asecond RS are quasi co-located according to a second of the sets oflarge scale channel properties.
 10. The UE of claim 9, wherein the setsof large scale channel properties each include at least one of a delayspread, a Doppler spread, a Doppler shift, an average gain, or anaverage delay, and wherein the configuration information is transmittedvia a radio resource control (RRC) signaling.
 11. The UE of claim 9,wherein the first set of large scale channel properties is associatedwith an RS configuration corresponding to the first RS, and wherein theRS configuration indicates a RS pattern for the first RS.
 12. The UE ofclaim 11, wherein the RS configuration includes a number of antennaports and a scrambling identity.
 13. The UE of claim 11, wherein RSports of the RS configuration are quasi co-located according to largescale channel properties including a delay spread, a Doppler spread, aDoppler shift, an average gain, and an average delay.
 14. The UE ofclaim 11, wherein the RS pattern corresponds to a type of time andfrequency allocation for one or more RSs of the RS configuration. 15.The UE of claim 9, wherein a RS pattern of the first RS is configured byhigher layer signaling, and wherein the first RS comprises a channelstate information-reference signal (CSI-RS).
 16. The UE of claim 9,wherein the at least one processor is further configured to: receivedownlink control information (DCI) including bits on a physical downlinkcontrol channel (PDCCH) from the base station via the at least onetransceiver, wherein the bits indicate a RS configuration among RSconfigurations specific to the UE and one of the sets of large scalechannel properties.
 17. A method performed by a base station, the methodcomprising: transmitting configuration information for sets of largescale channel properties to a user equipment (UE), wherein a type ofeach of the sets of large scale channel properties is one of a pluralityof types including a first type and a second type, wherein, if the typeis the first type, the set of large scale channel properties comprises adelay spread, a Doppler spread, a Doppler shift, and an average delay,and wherein, if the type is the second type, the set of large scalechannel properties comprises a Doppler spread and a Doppler shift; andtransmitting a demodulation reference signal (DM-RS) of a physicaldownlink shared channel (PDSCH) to the UE, wherein an antenna port ofthe DM-RS of the PDSCH and an antenna port of a first reference signal(RS) are quasi co-located according to a first of the sets of largescale channel properties and the antenna port of the DM-RS of the PDSCHand an antenna port of a second RS are quasi co-located according to asecond of the sets of large scale channel properties.
 18. The method ofclaim 17, wherein the sets of large scale channel properties eachinclude at least one of a delay spread, a Doppler spread, a Dopplershift, an average gain, or an average delay, and wherein theconfiguration information is transmitted via a radio resource control(RRC) signaling.
 19. The method station of claim 17, wherein the firstset of large scale channel properties is associated with an RSconfiguration corresponding to the first RS, and wherein the RSconfiguration indicates a RS pattern for the first RS.
 20. The method ofclaim 19, wherein the RS configuration includes a number of antennaports and a scrambling identity.
 21. The method of claim 19, wherein RSports of the RS configuration are quasi co-located according to largescale channel properties including a delay spread, a Doppler spread, aDoppler shift, an average gain, and an average delay.
 22. The method ofclaim 19, wherein the RS pattern corresponds to a type of time andfrequency allocation for one or more RS s of the RS configuration. 23.The method of claim 19, wherein a RS pattern of the first RS isconfigured by higher layer signaling, and wherein the first RS comprisesa channel state information-reference signal (CSI-RS).
 24. The method ofclaim 17, further comprising: transmitting downlink control information(DCI) including bits on a physical downlink control channel (PDCCH),wherein the bits indicate a RS configuration among RS configurationsspecific to the UE and one of the sets of large scale channelproperties.
 25. A method performed by a user equipment (UE), the methodcomprising: receiving receive configuration information for sets oflarge scale channel properties from a base station, wherein a type ofeach of the sets of large scale channel properties is one of a pluralityof types including a first type and a second type, wherein, if the typeis the first type, the set of large scale channel properties comprises adelay spread, a Doppler spread, a Doppler shift, and an average delay,and wherein, if the type is the second type, the set of large scalechannel properties comprises a Doppler spread and a Doppler shift; andreceiving a demodulation reference signal (DM-RS) of a physical downlinkshared channel (PDSCH) from the base station, wherein an antenna port ofthe DM-RS of the PDSCH and an antenna port of a first reference signal(RS) are quasi co-located according to a first of the sets of largescale channel properties and the antenna port of the DM-RS of the PDSCHand an antenna port of a second RS are quasi co-located according to asecond of the sets of large scale channel properties.
 26. The method ofclaim 25, wherein the sets of large scale channel properties eachinclude at least one of a delay spread, a Doppler spread, a Dopplershift, an average gain, or an average delay, and wherein theconfiguration information is transmitted via a radio resource control(RRC) signaling.
 27. The method of claim 25, wherein the set of largescale channel properties is associated with an RS configurationcorresponding to the first RS, and wherein the RS configurationindicates a RS pattern for the first RS.
 28. The method of claim 27,wherein the RS configuration includes a number of antenna ports and ascrambling identity.
 29. The method of claim 27, wherein RS ports of theRS configuration are quasi co-located according to large scale channelproperties including a delay spread, a Doppler spread, a Doppler shift,an average gain, and an average delay.
 30. The method of claim 27,wherein the RS pattern corresponds to a type of time and frequencyallocation for one or more RSs of the RS configuration.
 31. The methodof claim 25, wherein a RS pattern of the first RS is configured byhigher layer signaling, and wherein the first RS comprises a channelstate information-reference signal (CSI-RS).
 32. The method of claim 25,further comprising: receiving downlink control information (DCI)including bits on a physical downlink control channel (PDCCH), whereinthe bits indicate a RS configuration among RS configurations specific tothe UE and one of the sets of large scale channel properties.